Severino I think is legit - think it had a lot to do with throwing at high velocity late in games - over-extending his arm. Any arm can only endure so much, had so many pitches & fewer high velocity. Thought the problem actually started around AS break last year when he was struggling.
Betances never got in game ready conditioning before ST - using the new baby as his reason. I reserve judgment on Stanton but find it strange that no one is discussing it. Not sure whether it's waiting for test results or he doesn't want to go public yet. There is so little privacy in this age.