Probably not. I'm just telling you my observation.
And you're pointing out a problem without offering a solution. Your advice to OP is "don't link to Golfnow". So I suppose they should do what you do and just link to the course homepage... which links to Golfnow? What does that accomplish?
In any case, the golfnow.com is not what most people use to find courses. OP even said they are building their search app because "Google filters for golf course results are terrible". Not because golfnow.com searches are terrible. Golfnow is for booking, for which there are other alternatives that courses can use.