VIVEでUIのボタンをクリックしたい

Question

前提・実現したいこと

VIVEでUIのボタンをクリックしたいのですが、現在開発している環境での方法がわかりません。
環境は
SteamVR Unity Plugin - v2.5 (sdk 1.8.19)とUnity 2019.2.9f1で開発しています

該当のソースコード

using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;
using System.Collections;
using System.Collections.Generic;
using Valve.VR;

public class LaserInputModule : BaseInputModule
{

	private SteamVR_Action_Boolean actionToHaptic = SteamVR_Actions._default.InteractUI;
	private SteamVR_Action_Vibration haptic = SteamVR_Actions._default.Haptic;
	//private SteamVR_Action_Vector2 TrackPad = SteamVR_Actions.default_tapd;
	private Camera UICamera;
	private LaserController[] lasers;

	private GameObject[] hitObjects;
	private GameObject[] pressedObjects;
	private GameObject[] dragObjects;
	private PointerEventData[] pointEvents;

	//------------------------------------------------------------------------------------------------------------------------------------------//
	protected override void Start()
	{

		base.Start();

		// GUI-Raycast用のCameraを作成
		UICamera = new GameObject("UICamera").AddComponent<Camera>();
		UICamera.fieldOfView = 5;
		UICamera.nearClipPlane = 0.01f;
		UICamera.stereoTargetEye = StereoTargetEyeMask.None;
		UICamera.clearFlags = CameraClearFlags.Nothing;
		UICamera.cullingMask = 0;

		// 全UIキャンバスにCameraをセット
		Canvas[] canvases = UnityEngine.Resources.FindObjectsOfTypeAll<Canvas>();
		foreach (Canvas canvas in canvases)
		{
			canvas.worldCamera = UICamera;
		}

		// ヒエラルキーからコントローラーを取得
		lasers = GameObject.Find("[CameraRig]").GetComponentsInChildren<LaserController>(true);

		hitObjects = new GameObject[lasers.Length];
		pressedObjects = new GameObject[lasers.Length];
		dragObjects = new GameObject[lasers.Length];
		pointEvents = new PointerEventData[lasers.Length];
	}

	//------------------------------------------------------------------------------------------------------------------------------------------//
	private bool GUIRaycast(int index)
	{

		if (pointEvents[index] == null)
		{
			pointEvents[index] = new PointerEventData(base.eventSystem);
		}
		else
		{
			pointEvents[index].Reset();
		}

		// UICameraのベクトルをレーザーと一致させる
		UICamera.transform.position = lasers[index].gameObject.transform.position;
		UICamera.transform.forward = lasers[index].gameObject.transform.forward;

		// UICameraの中心からUIキャンバスへレイキャスト
		pointEvents[index].delta = Vector2.zero;
		pointEvents[index].position = new Vector2(Screen.width / 2, Screen.height / 2);
		pointEvents[index].scrollDelta = Vector2.zero;

		// ヒットテスト
		base.eventSystem.RaycastAll(pointEvents[index], m_RaycastResultCache);
		pointEvents[index].pointerCurrentRaycast = FindFirstRaycast(m_RaycastResultCache);
		m_RaycastResultCache.Clear();

		return pointEvents[index].pointerCurrentRaycast.gameObject != null;
	}

	//------------------------------------------------------------------------------------------------------------------------------------------//
	public override void Process()
	{

		// 全UIキャンバスとレーザーのヒットテスト
		for (int index = 0; index < lasers.Length; index++)
		{

			// 現在選択中のUIの選択を解除
			ClearSelection();

			// レイキャスト & ヒットテストを行う
			bool hit = GUIRaycast(index);
			if (hit == false)
			{
				lasers[index].AdjustLaserDistance(0);
				continue;
			}

			// ヒットしたオブジェクトを保持
			hitObjects[index] = pointEvents[index].pointerCurrentRaycast.gameObject;
			base.HandlePointerExitAndEnter(pointEvents[index], hitObjects[index]);

			// レーザーの長さを調整
			if (pointEvents[index].pointerCurrentRaycast.distance > 0.0f)
			{
				lasers[index].AdjustLaserDistance(pointEvents[index].pointerCurrentRaycast.distance);
			}

			// プレスダウンをトラック
			if (IsPressDown(index))
			{

				pointEvents[index].pressPosition = pointEvents[index].position;
				pointEvents[index].pointerPressRaycast = pointEvents[index].pointerCurrentRaycast;
				pointEvents[index].pointerPress = null;

				if (hitObjects[index] != null)
				{

					//プレス開始イベントの発行
					pressedObjects[index] = hitObjects[index];
					GameObject newPressed = ExecuteEvents.ExecuteHierarchy(pressedObjects[index], pointEvents[index], ExecuteEvents.pointerDownHandler);
					if (newPressed == null)
					{

						// プレスに反応しないUI用にクリック開始イベントを発行
						newPressed = ExecuteEvents.ExecuteHierarchy(pressedObjects[index], pointEvents[index], ExecuteEvents.pointerClickHandler);
						pressedObjects[index] = newPressed;

					}
					else
					{

						//クリック開始イベントの発行
						pressedObjects[index] = newPressed;
						ExecuteEvents.Execute(newPressed, pointEvents[index], ExecuteEvents.pointerClickHandler);
					}

					// 新しく押下したUIを保持する
					if (newPressed != null)
					{
						pointEvents[index].pointerPress = newPressed;
						pressedObjects[index] = newPressed;
						Select(pressedObjects[index]);
					}

					// ドラッグ開始イベントの発行
					ExecuteEvents.Execute(pressedObjects[index], pointEvents[index], ExecuteEvents.beginDragHandler);
					pointEvents[index].pointerDrag = pressedObjects[index];
					dragObjects[index] = pressedObjects[index];
				}
			}

			//ドラッグ中イベントの発行
			if (dragObjects[index] != null)
			{
				ExecuteEvents.Execute(dragObjects[index], pointEvents[index], ExecuteEvents.dragHandler);
			}

			// プレスアップをトラック
			if (IsPressUp(index))
			{

				//ドラッグ終了イベントを発行
				if (dragObjects[index])
				{
					ExecuteEvents.Execute(dragObjects[index], pointEvents[index], ExecuteEvents.endDragHandler);
					if (hitObjects[index] != null)
					{
						ExecuteEvents.ExecuteHierarchy(hitObjects[index], pointEvents[index], ExecuteEvents.dropHandler);
					}
					pointEvents[index].pointerDrag = null;
					dragObjects[index] = null;
				}

				//プレス終了イベントを発行
				if (pressedObjects[index])
				{
					ExecuteEvents.Execute(pressedObjects[index], pointEvents[index], ExecuteEvents.pointerUpHandler);
					pointEvents[index].rawPointerPress = null;
					pointEvents[index].pointerPress = null;
					pressedObjects[index] = null;
					hitObjects[index] = null;
				}
			}
		}
	}

	//------------------------------------------------------------------------------------------------------------------------------------------//
	private bool IsPressDown(int index)
	{
		//var device = SteamVR_Controller.Input((int)lasers[index].gameObject.GetComponent<SteamVR_TrackedObject>().index);
		//return device.GetPressDown(SteamVR_Controller.ButtonMask.Trigger);
		return actionToHaptic.GetStateDown(SteamVR_Input_Sources.LeftHand);
		


	}

	private bool IsPressUp(int index)
	{
		//var device = SteamVR_Controller.Input((int)lasers[index].gameObject.GetComponent<SteamVR_TrackedObject>().index);
		//return device.GetPressUp(SteamVR_Controller.ButtonMask.Trigger);
		return actionToHaptic.GetStateUp(SteamVR_Input_Sources.LeftHand);
	}

	//------------------------------------------------------------------------------------------------------------------------------------------//
	public void ClearSelection()
	{
		if (base.eventSystem.currentSelectedGameObject)
		{
			base.eventSystem.SetSelectedGameObject(null);
		}
	}

	private void Select(GameObject go)
	{
		ClearSelection();
		if (ExecuteEvents.GetEventHandler<ISelectHandler>(go))
		{
			base.eventSystem.SetSelectedGameObject(go);
		}
	}


}