So perhaps at the end of the day it comes down to people. There are a relatively large amount of not very competent people in every walk of life, or said another way, a bunch of very average people who we'd prefer they think a bit more about what they are doing and what it means.
I guess this is it, really. It's true that a lot of medical research is surprisingly bad, even when it's not about ME/CFS. Incompetence, and also the bias created by the prospect of financial returns.
There are probably some ME/CFS specific issues too.
It is not a prestige area. If you are a bright medical scientist, there are questions to answer that will see you better paid, better resourced and better recognised, questions to do with cancer for example. Only those with a personal connection to the disease or at least a good understanding of the need are likely to plow on with ME/CFS regardless. On average, our researchers probably aren't as good as the ones addressing more prestigious diseases. I think that also probably applies a bit to our funders and charities. In many cases, it's just whoever puts their hand up to do the (volunteer/poorly paid/low status) work.
Money to some extent could counter the lack of prestige - but, we don't have a lot of that, as ME/CFS hits young people of working age, and hits them with physical incapacity and shame-inducing stigma. People with ME/CFS and their families have tended to lose any power - financial, influential - that they had. People like many here at S4ME who call for things to be better tend to struggle to gain decision-making roles, even within our own charities. We don't have the well-resourced institutions like the cancer research institutes.
There is also prejudice. That affects the questions ME/CFS researchers want to answer, and to a large extent get paid to answer - e.g. Is it perfectionism? Will a mindfulness course fix it? How can we implicate cortisol in the pathology? Why don't we measure cytokines in blood again?
Sorry, off topic. To answer the question - yes, engineers might be useful for some research questions. But, there are skills and personal qualities more important than what degree the person did when they were young.