It will run into the problem that the B2B world is small for any given operator, making transactions a repeated reputational game. Named reviewers will not criticize because it only hurts them for future partnerships, and anonymous reviews are hard to substantiate. There's also enough money in this stuff for defamation lawsuits to enter the picture.
I'm not sure what a good solution could be, just that I've seen enough examples of trying to research a potential partner where you get one story from a loose acquaintance and a totally opposite view if you are lucky enough to have a good friend willing to give you the real story.
Also, a large player (customer) in a small market (say industrial repair providers) has a defacto monopsony, and can write bad reviews all it wants.
No legal payout will counteract the lack of future business, and worst case for them they can hire someone to do the work for them on their own payroll.
Perhaps some kind of insurance that pays for “fake” transactions. Industry members chip in to fund an insurance company. The insurance company would do business with a variety of companies from a variety of different “shell” companies, and appear normal to any observers, but its main purpose would be to provide reviews.
Take a look at Bungalow Living. I had to file a claim against them and won. Their BBB profile is pretty accurate though it could be more so if it were an F.
In this case the enforcement issue is that the other party can drag out the fight long enough to make the contract worthless.
The "war stories" section from this website are a great read.