How is it possible for a provider listing to have no reviews?  

...happens in situations like this where there's a brand new profile and there may have been a problem with the review so it was pulled, then fixed and posted again.  Meanwhile the profile remained.  You just happened to see the profile while the review was down.

I asked admin about it.  They said that the review had been removed (didn't say why) and they left the profile up in case someone else submits a review.