In theory a review hoster is supposed to evaluate claims and act on reasonable ones. In practice review hosters are terrified of getting sued and will take down reviews easily.
I suspect most local businesses hire "reputation fixing" firms to actually do this dirty work for them.
Aside: somehow businesses get moved - even major ones like a local McDo got moved to the wrong location. Takes weeks for corrections from when I report them. I really can't understand that one. This too could be a killer for a small business, getting shifted to the wrong location.
In a similar vein, I'm forever having to report our opening hours and things to Facebook as we don't have any (small craft shop, open by arrangement) and people insist on adding some.
It's all really weirdly handled. I suppose it's the presence of untrustworthy parties in such disclosures though Google should have enough trust signals to weight users input.
In any case, the scenario you're describing is decidedly not pay-for-play on Google's part, and thus doesn't really impinge on my response to OP.
I'll assume Google's reviews are at least somewhat likely to be biased (either way!) until reason to believe otherwise. The "you don't know the review wasn't posted by a dog" position.
Reviews can be removed if they are shown to violate Google policies. Also, legal action can be taken to remove a review. Google does not write law about what reviews are permanent.
I wish Google would be terrified of getting sued, but we both know this is not gonna happen.
My friend is a business owner.
She received couple one-star reviews on google maps from customers she never had (she’s a real estate developer, real estate is expensive, she doesn’t have many customers).
Wasn’t able to do anything about them.
Someone has given a credible mechanism for take down, report it as fraudulent. I find it highly likely that if you have a paying B2B relationship - eg you're a high paying advertising client, that you'd be able to report "frauds" and get immediate action.
But if course I've wouldn't know, and presumably Google would have NDAs for businesses in any special access (it would also be detrimental to the business to disclose it and risk losing the special access).
All we've really got is our TrustRank RTM on our part experiences with Google and similar corps.
And you used Google search to look for it, right? ...
(Kidding.)
And if your affiliation to this business is based on ad spend then well...
But if that doesn't work for you, pretend I called it an unsubstantiated implication instead. Either way, I think we all understood what the OP meant, and we all understood what I meant in my response. So at least we are communicating.
I'll let you decide if that implication is unsubstantiated or not.
Today you go out and there's a pigeon sitting on the branch over your car, you scare it away.
Your friend is like "what did you do that for, you have no evidence this pigeon poops on cars!".
Your [asdfasgasdgasdg] position is "this pigeon might be fine" the OP's position appears to be [or at least, mine is] "pigeons are probably going to poop on my car". You're saying his position is insubstantiated ...
It's the difference between treating Google as unique, and treating them as a member of a class of businesses. It's not insubstantiated, it's just a different form of substantiation. If all advertising businesses the OP has dealt with before were underhanded then your position looks to them like "today is unique, maybe the sun won't rise".
tl;dr you can substantiate a position based on general behaviours of items in a class, it's not necessarily wrong, and can be just a different model.
There is no way to do this that I can find documentation of on the public internet. You'd think if it were possible, someone would have written a howto guide. Personally, I'm deeply skeptical that any such mechanism exists. The revenue it would generate would be negligible and the potential for reputation loss significant.