I've seen R12 and/or R13 being burnt while the HV-section was still working.
But I think this is causing greater stress for the other components.

The WPC DMD HV section is notoriously under-engineered. It's de rigeur for them to smoke themselves even when there isn't any other fault. (Kind of how the GI section will eventually cook itself, so will the DMD HV.) It's so regular that I don't even bother with looking for a fault when I come across a burned up HV section; I just order a HV rebuild kit and install it. Only if it doesn't work then do I even begin troubleshooting further. (Your DMD itself is likely fine, btw.)

I agree with TheKorn. Its reasonably cheap to just rebuilt the HV section, good practice,probably needs done anyways or will need done.