I thought I identified the Kimmel clip that got him in trouble and it was all about Donald Trump’s lack of sadness over Kirk’s death as Trump prattles on about a new ballroom at the White House when asked about Kirk’s death. As usual with Kimmel,it was spectacularly unfunny but I am not sure I agree with taking him off the air, permanently anyway.
But maybe that wasn't the offending clip.
Or, maybe it is more of the Kimmel overview that the network dislikes. Nexstar cancelled the Kimmel showing and I assume Nexstar represents most of the affiliate stations. What the affiliates want is a big deal at the networks.