Your function that repositions the Vara does not know which specific Vara you want to move because you have just told it to move all of them when the function is called. If you are picking a specific instance of an object and you want to do something with that instance only, you need to put the actions within that same event or sub events after the picking has happened. Alternatively you can tell the function which instance you want it to affect but to do that requires extra steps and passing the instance UID as a variable into the function.
Easy option. Delete events 4,5,6&7. As a sub event under Event 2, add in the Vara is overlapping Collision condition (that was previously event 7) and then add the Vara set position to MenyBlock action (from the function) into that event.