Although it would be hard to prove if it happened, I don't think one is allowed to advertise 'discount for review' as it's more of a bribe, a "quim pro quo"
(almost the same as a "quid pro quo"), than a discount.
However, "discount for TER members" (regardless of promising to write a review) or some such is allowed. Now that I think about it, I guess she can use TER handle as part of her screening. I wonder if the following scenario is OK:
He: "I'm on TER but no published reviews."
She: "Oh, well, I prefer guys who write reviews so I can get an idea of what they like during a meeting. Call me some other time."
He: "I'm on TER."
She: "I checked your references and I read your reviews and I think we'll get along really well. I hope you'll review me, too, after my standard-for-all TER discount."
I think she can screen for likely reviewers but not bribe them.
(I also know some Providers that advertise a discount on the SECOND session AFTER the review gets published.