7:15 , and that's with burning oxygen by moving to unlock himself. Plus he had to hold the chains with his arms the entire time. He didn't had a good position. His body and his mind were destroyed by the 7 days he had been in there. He wanted to beat the record of 8:58 in these conditions. There was no way he could pull this off. That's why you can't say he failed, IMO it was impossible.
Still, he's doing things no one can explain. The dude can read your mind, and even more, he's amazing.