I'm not sure why one would compare reviews by acknowledged experts in a field with stuff written by anonymous randos, and it seems highly unlikely that anyone with the appropriate qualifications would be lurking on some mechanical turk-like site.

I'm also deeply suspicious of the confidentiality of anything sent to one of those sites.

However this does suggest the idea that a high-powered university in a low-income country might be able to cut a deal to provide reviewing services...

It’ll get you an electrician for about three hours in London. How long do these papers take to read critically?

You can get 50 reviews on Fiverr for that price!