It wasn’t a risk. A risk is when something could possibly turn out to be in your favor.
There was absolutely no evidence to overturn that call. None.
If McDermott challenged that he’d be called dumb for doing so by many and you know that’s true.
The Bills hired a guy to sit in the booth to review these things and let McDermott know. I’m pretty darn sure he let McDermott know the call would not be overturned.