Usually, this topic does stir up a hornet's nest, especially since the review you mentioned was significantly lower than the others in terms of ratings.  But you have been around longer here than I so you already know that.  There are lots of situations where this could and has happened.  In no particular order -  

Provider contacted admin and disputed the review.  Maybe the details were wrong or she never saw the reviewer - could just as easily be that she did not like the score (and I am sure in your time here, you recall those threads.)  It can also go the other way when guys use the review as a bully tactic or submit bogus reviews for VIP days.

Someone reported the review and it is down for internal TER review.

Another review done by the reviewer was disputed and pulled, which could lead to all of that hobbyist's reviews to be pulled. - example would include a hobbyist acting as a white knight, shill, or pimp in disguise.

Your memory has failed and you got your reviews mixed up with respect to providers or you have entered an alternate universe.

The reviewer requested to have it pulled for reediting and resubmission.

I am sure there are other possibilities.  Odd that you would post this question as you mentioned other reviews posted for this provider.  Was the allegedly pulled review done by a handle with multiple reviews or a handle known to you - how about the handles whose reviews still remain on her profile?  

I am kinda SMH at some questionable stuff related to reviews as well.  Not sure if I am just now finally noticing this or if it has always been as prevalent. - Seeing more reviews for ladies with only one review by a handle with only that particular review.  In another example and I can't recall the name, but recently saw a lady's profile with multiple reviews and each of the reviewing handles only had that one review.  Stranger still, the reviews were all similar in how they were written.   I guess she ruined them for anyone else.