The transfer form posts new_employee_id / new_location, but
storeTransfer() read to_employee_id / to_location. Both came back
empty, so every transfer wrote NULL over custodian_employee_id and
blanked the location — the asset ended up with no custodian at all,
and asset_custody_history recorded the move with an empty recipient.

Reads the names the form actually sends, keeping the old ones as a
fallback.