Given the timeframe, I think people are skeptical that 1. Elon arranged for twitter to contract with Tesla for code review and 2. Recused himself from the negotiations regarding scope of work and rate charged.
Who cares? The companies in his orbit benefit substantially from the cross pollination between them, and the PR opportunities that generates - much more than any arms-length negotiated rate would. Avoiding the type of fake work that you describe is very helpful for achieving the high iteration speeds his companies have.