all i can say is try to identify the part of the board thats damaged. i.e. if its near the heater relay check it out. and so on. solder it back together if its not too bad, then put a megger on the machine and try to find the fault.
what might be encouraging is that i’ve soldered up a couple of dishy boards lately and not found any cause and they’re still going yet.
i’m afraid i’ve no belling specific info though.