I read somewhere that JPM said they were gradually (every few years) adding some of the assets they got from WaMu to their financials.
They were keeping them in a separate category and not adding all of them at once.
Now, I don't know if this referred to mortgages (I assume it did) and I don't know what kind of "category" they could be put in, but they somehow did it and it's considered legal.
I'm not an accountant, and have no idea if this means you're wrong, but I do know that things can be hidden very easily and legally, and we really need a CPA to give an opinion before we start getting too excited.