So basically GOX lost the Keys to the cold-cold-cold-cold wallet with 750k BTC in there?
If that document is legit and in January they were ready for a big expansion then suddenly they have no bitcoins? Yeah, maybe they just lost the keys or they were corrupted somehow.
Banking regulations in Japan could indeed cause a backlog in withdrawals, but then this whole vanishing bitcoin issue arose. BTC withdrawals were unaffected until quite recently, right? It was just fiat that was delayed?
But who knows. Maybe they had some deceptive plan to open affiliate exchanges to bring in new BTC to lower the ratio of missing BTC.