Well I think the only reason he was able to tough it out, and keep fighting is because he was already in the fight, high adrenaline, etc.... in training I bet he would have tapped to something like that. And although it clearly had an impact on him in the further rounds, it almost looked like he was over it by the end of the fight, and whether he was posturing or not, he did say it wasnt that bad. I've seen people have their arms broken from bicep crushers before though, and he wanted to finish the grappling match (it was a competition and he hadn't yet seen his floppy arm).
Also the submission is more of a compression submission rather than a twisting one (heel hook) so typically it attacks the calf muscle more than the knee itself (although apparently your entire knee can "explode") I've seen people have their arms broken from bicep crushers before though, and he wanted to finish the grappling match (it was a competition and he hadn't yet seen his floppy arm).
As for him finishing it, its hard to say if he could have finished with that particular submission, he almost comes up on top at the end, but it's probably fairly difficult to come up on top of tyson griffin like that, and had he switched to another submission he may have lost it (tyson griffin can scramble). I mean in fights there is always what if's. I remember at the time of the fight it being extremely interesting and making the fight that much more exciting though.
