He claims to have lost over 4k bitcoins, how is that very good coding skill? (we know he stole it, but how can you call him a good coder when he says he lost it?)
I believe he was a decent programmer. Even if this wasn't a inside job, it doesn't make you a bad programmer that you missed something which someone else found out. Peoples brains operate differently, or may be more skilled. It doesn't make him a bad programmer.
Although, for holding such a large amount of coins, he should of invested in some penetration testing. (He might have) But, as far as I'm aware he coded it himself and probably didn't think it would be a problem checking for security issues himself.
Sadly, I too had money stored there. Which I didn't get back (lucky I was wise enough not to store much there), But I'm not going to go throw shit at the wall and call him a bad programmer. I might.
It doesn't matter if I believe he stole it or not, we can't prove it and we are speculating.