B-Man's the closest. You have to understand, Fox is an industry. They manufacture fear and paranoia, because it sells well (gets those viewers watching the news and buying gold). For the most part, they don't care all that much about Muslims. They probably buy into the narrative at least a little (if only to help themselves sleep better at night), but their primary purpose is to keep making money. They're going to distance themselves from Linn like he was carrying ebola. If it was a little less cut and dry, they might try to argue that he's a hero, or even if he hadn't brought up Fox they might try to shift blame to liberals and evil terrorists ("he was so afraid of Al-Qaeda's evil plot that he went a little unhinged, but can you blame him?"). But because he directly implicated Fox News, they have to do some damage control, and that's going to mean discrediting him. You can expect them to start talking about personal responsibility, liberal lawyers trying to make them look bad, and even false-flag democrats working to destroy the reputation of good, hard-working conservatives.
They can wink and nudge and hint at violence and racism, but they can't afford to go full Klansman and openly advocate without alienating even some of their viewers. You have to understand, a majority of their viewers honestly don't see themselves as racist or violent. They rationalize it as innocently as possible. This lets Fox deal, effectively, with two audiences: one of open racists and assholes, and one in denial. The ones in denial remain the larger part of the audience, so Fox has to maintain that illusion for them. Don't tell the kids that Howdy Doody isn't real. They won't buy their Wonder Bread. Don't tell the old white people that Fox is racist. They won't buy their gold and silver.