Also there's a good chance that the decision to go with IBM as a vendor, and the conduct thereafter, was corrupt from the start. That would go a long way toward explaining why so little due diligence was observed in assessing whether or not to continue the project with them at any of the stages it could've been.

Yes, people do make huge blunders in powering forward with overpowered, unnecessary solutions to problems they largely do not have; but blunders this big usually don't take this long to suss out.