I don't think this is true. I believe we control our own destiny, assuming Pitt holds this lead.
You are correct.
If Baltimore wins out they win the division and since we have the tie-breaker over Cincy, the Wild Card slot will fall to us (providing we win out as well).
Note that if Cincy wins out and Baltimore drops a game (against Cincy) and the Dolphins drop a game, the tie-breaker goes to Baltimore UNLESS the Chargers win out. Then it becomes a 3-way and our head-to-head against the Ravens no longer applies. The Dolphins WIN that tie-breaker on conference record.
All Most possibilities:
10-6 Dolphins win out:
+ Patriots lose out ----> Dolphins win AFC East.
+ Patriots win 1+ ----> Dolphins get a Wild Card.
9-7 Dolphins drop a game (doesn't matter which):
+ Ravens win out + Cincy drops both its games ----> Dolphins get a Wild Card.
+ Ravens win out + Cincy wins a game ----> Cincy gets the Wild Card.
+ Ravens drop a game + Cincy drops both its games ----> Dolphins get a Wild Card.
+ Ravens drop a game + Cincy wins one or both + Chargers win out ----> Dolphins get a Wild Card.
+ Ravens drop a game + Cincy wins one or both + Chargers lose one or both ----> Ravens get a Wild Card.
+ Ravens drop both games ----> Dolphins get a Wild Card.
8-8 Dolphins drop both games:
Somewhat complicated, but the Dolphins could still make the playoffs with 8-8.
The Dolphins lose the 8-8 shootout to the Jets, no matter what.
The Dolphins lose the 8-8 shootout to the Ravens, providing the Chargers or Steelers are not in the mix (in which case the 'phins win).
Note regarding the Jets: They would only hold the 8-8 tie-breaker over the 'phins and Chargers. If either the Steelers or Ravens win just a single game, the Jets are eliminated.