Well for starters you talked about how he and/or his post is not credible. You also stand up for the outfitter. Who's to say you don't work for said outfitter just like you say he may work for a competitor?
All in all we don't know. I know that "hit and run" reviews happen but like I said sometimes a bad experience is what gets the person to get online and post. All reviews can help in the end whether they are bad or good and as you said above don't form an opinion on one guys review. The collective body of work should be looked at when doing any kind of collection of data for finding the best fit for the person looking for an outfitter.
Also the guy did show back up after his initial post and seen all the bad hype about his post and then hasn't been back. Like I said more members get pushed away because of what they first post here than any other forum based site that I have seen. Look at how this site was just 6 or 7 years ago compared to now. There are other ways to go about finding out if the poster is just a drop and go without "bashing" what he wrote is all I am saying. Now on the other hand if the outfitter wanted to get on and defend himself that would be something different all together.