Considering just recently a bunch of chinese PV converters have been found to contain extra parts not in the schematics and can be made to create overvoltage remotely, without leaving evidence, I wouldn't dismiss the possibility outright.
I mean, it wouldn't have caused the failed voltage regulation itself, but it is realistically possible the initial cause of overvoltage was a hack.
Worse, some dumbass set the "Join their wars" to "All" instead of "None"