If either the Steelers or the Ravens win out, which one of them can't, the best they can be is 11-5.
The Bengals need to win 3 of the next 5 to clinch, as of now to be 11-5. They have the tie breakers. There's no reason they shouldn't be able to do that, looking at their schedule.
If some other teams want to help out, that's cool too....the Bengals need to take care of business. The wildcard will take care of itself.