Finding good SEO freelancers on Upwork

How do you determine whether Upwork SEO freelancers are any good?

I posted a job and got a wave of wide ranging quotes. Some of them were really obvious $5/hr boilerplate automatic tool SEO sorts of people, so I dumped them immediately. I ended up landing on one guy who charges $20/hr who laid out a SEO plan for me that seemed to make sense, but I have no idea if there is a good value add there. A lot of what he is doing is still automated through tools but I wonder if he will give me sound advice.

This particular freelancer, and many of these freelancers, have $100k+ earned and 99%+ job success score. Is this some kind of manipulation of ratings? In other contexts, those are usually incredibly strong indicators that a freelancer will deliver (e.g., for software projects I've run for my other businesses). I've had great success with low cost, international freelancers with good ratings. But in SEO, because there are so many who responded with profiles like that, I feel like something fishy is going on.

As background: I run a few blogs. I am an informed, but not proficient, at SEO. Meaning, I understand most concepts and understand Google's EAT, have a good sense of quality vs. crappy content, and otherwise been exposed to a fair amount of material on SEO. I don't know much about technical on-site SEO like schemas and such, don't really know formal methods around internal linking, and don't really know how to do backlink building effectively, as some examples of my knowledge gaps. I would do some of this stuff myself, but I'm time constrained and looking to outsource as much of my online business building as possible.