Darlington is a good writer and good TV personality who has strong connections inside the Dolphins. When he says something--good or bad--its almost always true. I understand why Gase would say something like that, and I completely believe Darlington that Gase did say it. Unfortunate that the injury happened, but that's just how the breaks go sometimes.
There's a lot of nay-saying about Ryan Tannehill, but the proof is in the performance. Here's a video of his 2016 performance. It's a youtube thing, so it doesn't show the INT's, but after the first 5 game adjustment period, I think he only had 1 INT and only lost 1 game anyway, so it's almost complete. Enjoy.