Yes, I understand the "risk" but I've been fortunate in that I've had amazing success seeing companions with no reviews anywhere. You mention Grace Harlow. She's fantastic and amazing. I have no problems recommending her to someone who can appreciate the experience she provides BUT if you're looking for a "sure thing" kind of experience, with specific services known in advance, I would recommend Ms Harlow. I haven't met the other ladies on your list, but I suggest picking ONE and see how things go.
There's nothing wrong with "knowing" what will (or could) happen before you spend that kind of money so I don't blame you for having some reservations.
As for myself, reviews are cool but I tend to focus on the "vibe" I get from the person. That comes from our communication and the "feel" I get from their overall presentation. For example, one of the things that caught my eye with Ms Harlow was the copy in her Tryst ad. The "Booty. Banter, Bourbon." line caught my attention and the line about "brimming with dad jokes". Those things told me she might be a bit lighthearted and fun. When we met for the first time, we laughed and I told her a couple of jokes. She was very chill and eased me into things nicely.
Another tip: if at all possible, try to book a slightly longer date. (At first I didn't use the word "date" in favor or "session" or "appt" but I find "date" helps to setup a good headspace for this kind of encounter

). If possible a lunch or dinner date. At least more than one hour. That helps "break the ice" a bit and let's her know you're not there "just" to "jump her bones". If she's into that, that WILL happen in due time and it will be all good.
Twitter/X might be another "indicator". If they are simply posting re-tweets of ads and not posting anything themselves, that might be a "flag" of something. If they are engaging with people and posting thoughts or snipets of life experiences, that can give you some insight into their personality which can help when spending intimate time with them.
Anyway, just my thoughts.

Good luck!