While I disagreed with going for two from the 7 and the 3 1/2, because I thought it was emotional and not logical, one take I read kind of turned me in favor of it a little more, even if it's not one Campbell would ever cite to.
With the division and playoffs secured, it's possible the juice wasn't worth the squeeze from an OT period. If you enter OT, you might have a slightly better chance at winning (relative to converting a 2pt conversion from the 7 or the 3 1/2), but you also have a much higher chance of sustaining a season-killing injury. Leave it all on the line, go win it with your offense. Twice. Because the refs didn't hear you the first time.