This is just speculation, but the BS&K investigation, once it's released to the public, could be the wild card here. BS&K, in this instance, given that they are/were paid by SU, might end up being viewed in the same light as Fitch, Moody's, S&P, etc. that rated the SIVs, CDOs, et al AAA to hold on to their clients who had put that worthless junk together and sold them to unsuspecting pension funds and other investors: keeping their clients happy, thus insuring the fat fees kept coming, was more important than telling the unvarnished truth. If so, BS&K and SU will take the hard fall.
Time will tell.