I dunno how well Mikey knows Alit games to know that he often includes town jailer. So that makes the claim kinda believable. His reaction to me thinking he has been softing cop also seemed fairly genuine.
The thing that has me paranoid is like, how do you turbo Kirino and even after Ex says that if Kirino is town than Mikey is scum and Mikey said he was a bit nervous after that, you don't double check he was your target. Though I guess I could kinda see Mikey doing that.
We've had either someone stopping the nks (so doctor, roleblocker, or jailer), or mafia is playing a long con risky move after the Rag lunch d1 and just not killing to set up fake claims. The first seems more likely, but there are some people I wouldn't put the second past.
I think I'm just gonna believe Ex is town the rest of the game. For the fact that he seems to also have picked up on Mikey's softing. And if Mikey is actually town then Ex most likely is too.