Them losing to one of the 4 AFC teams doesn't give us the tiebreaker. The first tiebreaker after divisional record is common games and yes, while they lost to the Jets, we cancelled that out by losing to the Cards.
Here are the common games:
Bills
Dolphins
Cards
Seattle
Jets
Rams
Patriots
San Fran
Cowboys are currently 4-2 (49ers, Cards) in common games, Eagles are 4-2 (49ers, Jets). If we lose one of the Buffalo or Miami games and Philly beats the Cards and Seahawks, we lose first tiebreaker after head to head and divisional record. In that scenario, we'd need the Giants to win a game to give us the divisional tiebreaker.
And they don't play the Lions, they play the Cards.