The combination document can be serially number - if they are created by a printer using NCR (carbonless) paper in pads - the top copy is sent with the goods. The duplicate remains in the pad and becomes the legal serially number register.
The point is, you don't create accounting Delivery Notes or Goods Receipts for inventory on consignment. you create non-accounting Delivery Notes / Good Receipts - similar to a courier who drops off a package and then returns the package a few days later. All legally documented but not accounting transactions.
The contents of the package (the inventory item) is tracked by the Production (Conversion) Order and that is the only accounting transaction required
NO I don't understand why you keep insisting on doing artificial accounting. As previously admitted - you have to ignore the values shown under Qty to receive and Qty to deliver - how unprofessional to maintain a set of account where certain inventory values aren't valid - supported by reality.
You haven't sacrificed few features, you have committed to maintaining unprofessional non-accounting standard sets of accounts which contain invalid inventory data.
If you were genuinely interested in improving the productive time of an employee which also maintained appropriate accounting standards then by now you would have adopted the solutions provided which you initially requested.
To me, to have the employee process one genuine accountings transaction (the Production (Conversion) Order) is far more efficient then having the employee process two artificial irrelevant accounting transactions (Delivery Note & Goods Receipt) which corrupt the accounts.