The release of Felt's name prior to his death greatly diminished the value of Woodward's book.
As to whether whatever profits should be shared with the source in such a case, I have no feeling because I have no sympathy for either party.
Felt violated his oath to release information to Woodward. He had other options if he wanted to get the truth out. And it has nothing to do with him getting or enjoying any wealth from his new notoriety. It's all about his heirs trying to get a bunch of money into his estate before he dies in the near future.