A task executer can only be connected to a single navigator at a time. So the only way I see to make the truck move in the 3d model is use kinematics.
To sync the travel time to that on the map you will have to determine the travel duration and use that to set the travel speed of the kinematic.
A good approach might be to listen to the "On Start Task" event, since that will allow you to read the task executer's current map position before the travel starts and that value is overwritten.
GIS_mirror_travel_with_kinematic.fsm
Note: In version 23.0, the "getCost()" method of the newly added "Navigator" class can be used to get the travel duration on the map, instead of using "function_s()".
token.TE.as(TaskExecuter).navigator.getCost(token.curPoint, token.destPoint, 2)