The question is not whether the airplane was tested beyond the arbitrarily chosen alpha-max incorporated in the FCS software in normal law. Of course it was flight-tested beyond alpha-max, either in alternate law, direct law or with some 'experimental' development version of the FCS software as suggested by OwainG.
The surprise for me is that apparently the special conditions under which the A320 was certified specify operational speeds such as V2 and Vref referenced to a Vs1g that can not be demonstrated with its systems operating as designed, i.e. in normal law. In other words, alpha-max is not determining Vs1g as it would have been under later regulation, but was selected somewhat independently.