Barhopper
Did you put a queen or cell in the split?
Just a thought, not the solution and open for opinion, if the split has a queen then if you bring it back and place it beside the original hive , then will the bees orientate to the position and return to the smell of their queen and so end up in the right hive.
Bees on pallets, some times 4, with little differentiation between boxes end up in the right hive, by smell?