Massie has donated a lot to Ron, and he's already shown his disdain for legislation like NDAA/SOPA/PATRIOT Act, etc. He may be more like Rand than Ron on foreign policy, but those differences are minor.
If you require someone to openly endorse Ron to get your support, then Massie isn't your guy. But I'm not going to fault him for that; I know the political reality of elections like this.
I, for one, will be supporting Thomas Massie not because of who he endorses, but because he will stand up for my constitutional rights while in Congress.