processing subinventory transactions through the mtl_transactions_interface

we are building an interface between our manufactoring legacy system and oracle to perform the shipping execution to a point where the order line is picked/staged and loaded into an LPN so the ship confirm can be executed in Oracle

our inventory is moved from a consigned inventory to staging in this processes--I cannot load the LPN in consignment since it is not LPN controlled--and the api for packing lpn's in wms does not move inventory so I am doing a subinventory transfer to load the lpn and move it to the staging subinventory

I keep getting a transaction processing error when relieving reservations--I can delete the reservations record and it will work but I don't understand what I am missing in the scrpt