You are right. We don't know the rest of the story. Perhaps Trump knows a lot more about Comey and what he has been saying and doing to trash Trump. There was one report that had Comey calling Trump crazy when he tweeted about Obama administration "wiretapping" him. It turns out that Comey may have used the phony Steele dossier, a product of Dem operations research, to justify the FISA warrant last July.
Take a look at the 17 pages of Grassley letters to the FBI at this link. It is eyeopening.
Rove is part of the GOPe. They have a lot to lose if Trump is successful in draining the swamp.
I gotta tell ya just in normal surfing I find so much jeopardy for Comey. He was a classic screw-up. He was involved in everything and most of it was messed up.If you needed 20 or 25 good reasons to fire him they are all there.