It wasn't lucky. it's a basic kick.. that won't normally work cause it's the least used weapon of MMA and most fighters won't stand squared up with an opponent..
As for any comments about Vitor losing....
"When you lose.. say little... when you win.. say less" - Hughes
It is because you chose to get on the mat that makes you the winner. Think about how many people are not on that mat right now. - Luis Sucuri Togno