I know you said you give up, but I totally disagree. What you're talking about is tax accounting 101, not reality.
Here we have a basic math equation:
If Joe Smith shoots Walter Doe dead with a 12 gauge shotgun, how much did it cost Joe to kill Walter?
Shotgun + Bullets = Answer.
Joe Smith ended up getting life in prison and 20K in court fees, but the original answer stays the same.
Shotgun + Bullets = Walter Doe dead (or, film finished)
Whatever happens after that has nothing whatsoever to do with Walter Doe being dead or your 10K film being finished.
That isn't what he's talking about.
He's talking about what needs to be paid to people for their part in the production of the film. Even if it takes place after production, it's still a production cost, because you agreed to it as a condition to them participating. No participation, no film.
If you build a house on loan and put a down payment in, the house gets built, and you get into the house -- but you continue to pay on it. That's the cost of the house.