I guess family reasons would do it. Any REALLY serious personal issues that just couldn't be avoided....but I'm pretty sure he has a cell phone, no?
I see no reason why he couldn't have taken 5 seconds to make a call, no matter what the reason....unless he was seriously injured, or a close friend/family member was in dire, DIRE need of 100% attention.
As for the loss, of course he has no one to blame but himself, and a better fighter...he was quite clear on that front after the fight. These are two separate issues.
He just doesn't have great sub defense, especially against triangles, apparently. Maybe three free months at the Lair will get that up to speed!!