How do I make the marble teleport to a certain area upon hitting an object

This is different from the teleporter trigger in PQ: The teleportation instantly happens when the function (shapename)::onCollision(%this, %obj) is executed. The destination point is just another named object just like the regular teleporter triggers. It may be useful for reducing the object count, or creating teleportation triggers that aren't shaped like cuboids (such as a spherical portal/wormhole). Do I just bring in the code for the trigger and paste it into the shape datablock's collision function?

Your onCollision should have a %col parameter, the marble. Store the destination position you want on the collided object as a dynamic field. Then just use %col.setTransform(%obj.destination) and add whatever extra effects you want, perhaps a playing a sound or setting the camera yaw, which could also be in dynamic fields.