AFAIK Mt. Gox was coded by Jed and a lot of non-Japanese bank accounts are holding their fund. Mark was actually running CallyHost and he suddenly jumped onto the bandwagon. As a CEO he is definitely responsible for the failure now. But was the whole thing within his grip ?
yes, yes he is. Read the Wired article –
http://www.wired.com/wiredenterprise/2014/03/bitcoin-exchange/"Ver and Powell were set to work through the weekend, but when they arrived at the company’s tiny office that Saturday, there was a surprise.
Mark Karpeles had decided to take the weekend off. The two volunteers were flabbergasted. “I thought that was completely insane and demoralizing for the rest of the team,” Powell remembers. On Monday, Powell says, Karpeles did return to work, but he spent part of the day stuffing envelopes. “I was like: ‘Dude why are you doing this? You can do this anytime. The site is offline. You need to get the site online.’”"