No, actually I don't think would have been a good strategy. If Obama sues to overturn a judgment, it means he's arguing against the state. At best the state would only have a superficial interest in defending this on appeal. The better option is for skeptics and challengers to appeal where more evidence can be presented and the weakenesses of Ankeny can be attacked. Malihi may have done this issue a favor because he left open Obama's bona fides.
This is an aspect I hadn't thought through. We could file Amicus Briefs, but that is not the same thing as arguing the case ourselves. The State Attorney could just roll over and put up token resistance. I suppose you are right.