At the time, I thought the triangle looked odd. It's not very tight and Chael tried the Team Quest tap to escape. That being said, I don't feel this was a fixed fight situation as much as it was a matter of Chael's well-documented psychological problems.
Chael has struggled with mid-match anxiety on multiple occasions. He has also given up in moments where he doesn't really have to. He sometimes gives in to the pressure of a situation as much as to the physical realities of a fight. This can't be proven of course, but I always felt Chael let the situation get to him in this moment against Anderson. The gravity of the win, his becoming champion, the massive buildup, his newfound popularity, the knowledge that he was on PED's, all of it. I don't think Chael was ready for nor thought he deserved the moment. I think he was afraid of the moment. He's one of my favorite fighters of all time, but I've always felt this way about him. There are some fights he's prepared to win going in and others he's prepared to lose. This is just my personal theory.