[mplanchard]

Again, if the police have sufficient evidence to convince a judge that a warrant is justified, it doesn't really matter what the evidence is, only that it is not misrepresented to the judge and that the judge deems it sufficient.

The main problem in this case was the fact that the police misrepresented their evidence to the judge. It is theoretically possible that a judge may have issued a warrant on the basis of the facial recognition tool, in which case the evidence from the search would not necessarily need to be thrown out. If that were the case, I'd expect the defense to appeal the validity of the warrant, in which case all the questions you're asking would come into play.