Where exactly did he say anything remotely violent
That's the deciding reason he got shut down too. Absolute inability to read the "room", even though what he said would be ugly at any point.
You can watch the monologue here https://www.youtube.com/watch?v=-j3YdxNSzTk&t=122s
I've seen the clip, now you go see what the authorities have figured of the killer; Absolutely nothing points at the murderer being maga, but pretty much every detail points towards him having been radicalized by the left. Unless you're just going to ignore people that knew him saying he was a leftie, Bella Ciao carved in to the bullets, and the very obvious of him having shot a right winger who was managing to change people's minds, etc.