I think is simply a matter of him fearing for his safety. It was an egregious incident with huge implications (Super Bowl berth) that he's being protected from a possible attack. It only takes one jacked fanatic.
There is no conspiracy. It is just a case of the NFL taking reasonable precautions to protect Vinovich's safety.
All teams will be on the wrong end of a bad decision, but it almost never directly results in the affected team missing out on a Super Bowl, nor prompts (misconceived) lawsuits, or protests involving tens of thousands of people taking to the streets.
Why put him in that position when, as a league, they've got more than enough officiating crews to avoid that outcome?