Did the Handshake actually happen?
This was my only problem with the movie. The brothers have dealt with him before, know he's a shady guy, and yet they still agree to an off the books handshake.
It sounds more like post-agreement regret after realizing how much McDonalds has gone on to make. It sounds very suspicious because a handshake agreement in front of business people/lawyers would actually be very easy to prove if it did occur as the movie portrays. It's as simple as getting sworn affidavits from people who were in the room when the deal occurred.