You all know as well as I do, aerobatics in a non aerobatic aircraft, flown properly and with precision, will pull no more g than a good steep turn.
However, you only have to "screw up" the maneuver and if you survive the aircraft may well be overstressed. Would the guilty pilot or crew own up and get engineering in to check the aircraft for overstress? Hell no. Claim up is the most likely but wrong, course of events. Here lies the problem and someone else has to strap their backsides to that aircraft.
Years ago in another life a cessna 180 flew to pieces that I knew of and it had been know to have been aerobated at some stage. Metal has a very long memory. Try and remember that.
If I catch anyone aerobating a non aerobatic aircraft I will do my up most to see the appropriate authorities are informed ASAP. Sorry but that sort of behaviour is just not on.