To suggest that the Bills have a religious litmus test is frankly rather absurd.
McDermott encourages players to open up about themselves with their teammates. Here is what Jordan Matthews had to say:
“Receiver Jordan Matthews took a risk when his turn arrived in Week 4. Matthews sent in the usual pictures—his mom and dad, brother, fiancée. And then … a photo of a cross, to represent his Christian faith. “When I sent them the cross, I was like, I wonder if they’re going to let me talk about [my faith]?” Matthews says. “Because this is essentially who I am.”
https://www.google.com/amp/amp.si.com/nfl/2017/12/01/buffalo-bills-sean-mcdermott-team-building-through-storytelling
Not sure why Matthews’ would have felt uncomfortable if it were a Christian locker room.