To be honest that sounds highly unlikely - washing machine (and all white goods) engineers are fairly basically trained, and it would be rare for one to have any understanding of electronics - basically it's a mechanical job with a little electrics thrown in.
This is why there's never been any spares availability for PCB's, and just a straight board swap. Although to be fair, it's gone mostly that way for other domestic electronics in recent decades - new stuff is too cheap to make it viable to keep spares and provide decent service.
The 'proper' makes of Microwave ovens often used to provide circuit diagrams of the electronics boards, but even then very few parts were available - but at least having a circuit gave you something to start from (if you were so inclined). Microwave engineers were basically washing machine type guys, so little electronics knowledge, so no need for components. We were different, we were TV guys doing Microwaves, as opposed to washing machine guys doing Microwaves.