"At this point 744,408 BTC are missing due to malleability-related theft which went unnoticed for several years."
This simply can't be right unless a few insiders were stealing them.
That document is FUD, guaranteed. I believe Mt.Gox are not solvent and will not survive on their own but that 744k BTC theft smells like BS like a lot of other stuff that doesn't make sense in that "leak".