The gift tax thing seems like a distraction. He would have needed to file a gift tax return for giving $10 million, but no taxes would be due. But he could just as easily have given $100 million, filed the return, and paid a large gift tax—he had plenty of cash floating around back then.
I guess what I’m saying is, it wasn’t a way to hide the gift, because it still triggered the need for a gift tax return filing.