They tend to send the #1 crew to the game that will be seen by the most households.
That still shrinks quite a bit when it's the network with the single game broadcast that week. When Aikman and Buck did the Washington vs Philly game it was only shown in the Northeast and Mid Atlantic states but didn't include NY, Boston or Baltimore. I think it will be the game shown in most of the West but won't be anywhere close to a national game.