No, that wasn't what the court case said. The case in question was talking about the exclusionary rule. In that case, a passenger did not give verbal consent to part of the search, but cooperated physically. The court ruled that the evidence found in that search was admissible.

There hasn't been any case along the relevant lines and it's not at all clear how the court would rule in such a case. The reason given ("testing the process") was enough to avoid application of the exclusionary rule when the subsequent search as a physical inspection of the passenger's feet. It most certainly would not be enough to require a cavity search to avoid a criminal charge. There's clearly some line in between those that a court would have to find. On which side would requiring a pat down to avoid a fine come? Hard to say.

From a practical point of view, such a case is highly unlikely to come up because the TSA has made it clear from their actions that they will not impose a fine in such circumstances, most likely because they don't want to see such a case litigated.