I hope one of the places I suggested works out, or that you are able to find a good fitter through word of mouth, which I think is usually the best way when it comes to medical providers.
As for what happened in your case that has left you where you are, I don’t know. It might call for an interested interogation of the historical data that exists, if your fitter had the time or proclivity for that. REM is the gold standard, but it does take some skill. I recall a clinician on these boards saying that he didn’t use REM because “you never get the same results twice”. This is untrue–I thought of him just the other day while looking at an REM measure that was identical 2 years after fitting. There are a lot of points of variability in hearing tests and hearing aid fits, and one needs to be sensitive to them. I can see how a clinician trying ernestly to implement REM but who works alone in a clinic with no mentorship/support might reject REM because they lacked the skills to troubleshoot it. If you cannot recognize that the gain response looks a bit funny at a certain frequency because of issues with probe tube placement, acoustic coupling, hearing aid positioning, and other various and sundry, then the approach would be to correct the gain at that point in the software even though correction is not required, and that can lead to some funny results. I would say, looking back, that my schooling on these issues was probably a bit lacking. So how does one come to a good place in this? Good mentorship, a particular curiosity, experience.
The other place where things can get weird is in how clinicians respond to patient requests. The part where a patient comes back and says, “I don’t like hearing [this thing that I am currently describing in a way that no other patient has described it]” and the clinician attempts to interpret that complaint and apply it to making changes in the software really is the “art” part of a fitting. There are no specific, 100%-agreed-upon ways to address each of these issues, just a general clinical consensus that is stronger in some cases and weaker in others presuming you can correctly interpret what the patient is describing. Users of this forum seem to put a high regard on their fitter “calling the manufacturer” about their problems, but the person on the other end of the call is also an audiologist providing their expert clinical opinion rather than some sort of magical manufacturer oracle. That expertise will vary just as anywhere else; manufacturer audiologists generally do have a strong training on the particulars of the individual software, but sometimes they have weaker clinical experience. This process of patient report and fitter adjustment can be magical sometimes, but I have also seen it get to some very weird places, particularly with young colleagues who are bending over backwards to try to make a patient happy. It’s one of the things I worry about when some users on this forum counsel others to go back to their fitter a dozen times to get things “perfect”.
So that’s just a long way of saying that there are a lot of points of failure and I cannot guess where things went off the rails for you.