Obligatory question at this point: Are you absolutely positive the site owners and everyone else involved are being completely forthright with you? It sounds as if you never set eyes on the site until after things went kerblooey, and then they came running to you for help. Is that right?
I'm thinking something analogous to a person withholding key information from the doctor because it's embarrassing and they really didn't think it could be relevant. And I can't help but notice that there seems to be a six-month hole in the middle of the narrative. What happened between now and last May?