I'm guessing this was motivated by backdoor accounting depriving Dwayne of some net/gross profit margins. This was a film that, in all likelihood, did squeak into profitability but since the DVD/rental market is in shambles due to streaming the usual studio act of "EVERY FILM IS A TOTAL BOMB!" paired with this brutal WB/DC cost cutting the studio wants to call it a colossal failure for tax reasons but Dwayne was counting on some money. Now he's blackmailed them into giving him some hush money so the tax deals can continue.