It is extremely unlikely that the pump coupler will have stripped. What is more likely is that the split pin which holds it in place was either not fitted or has come out. I think it would be possible for the coupler to slide forward in that eventuality.
Failure of hydraulics and PTO at the same time is often attributed to a clutch failure. Remove the inspection plate and look for anything amiss with the clutch. Also drain the oil and remove the RH side cover. Feel inside for the coupler. You should be able to feel if it has become disconnected. If you ascertain where the split pin hole is in the pump shaft you should be able to align the coupler and fit a split pin. It certainly won't be easy But I think that it could be done.
Let us know what you find.
DavidP, South Wales