I disagree.
In my opinion, they are rallying behind Incognito because Martin "quit" on them and any support for Martin would 1) make themselves look bad(they are selling an image after all) and 2) break up the status quo. Even players in Tampa are publicly supporting Schiano, and i dont think anyone can question how messed up that team has gotten(leaking medical records is vastly worse then anything thats happened here).
Not to mention the locker room was somewhat insulated. Granted, anyone could see whats happening had they looked hard enough, but most of their time at work would have been spent with position groups. Hell, even our quarterbacks would be more focused on chemistry with receivers and less concerned about their chemistry with the line.
Undoubtedly many of these players just want to get done with the interview, cause as few waves as possible, and put it behind them. If Martin was considered aloof and socially awkward(which i actually can see), they might find it more (personally) acceptable to lay blame on him then the scumbag-but-our-scumbag Incognito.
I think you're absolutely right that the things you're mentioning are a factor here. Perhaps even bigger factors. All I'm saying is that the narrative spun by Incognito Sr also fits into the picture. Every new development that comes out I'm going to be subconsciously checking against his story, looking for definitive inconsistencies or definitive confirmations.