From what we know, it is very clear that Wayne made a huge mistake and now is trying to reject the responsability on hosting dojo by writing the letters to everybody. Instead of honestly tell his friend about his fault.
I hope that this topic will help him to improve his jugment for next time
This is a good point as well... I happen to know there is more going on here than what has been publicly stated so I am not specifically referring to this case.
But when things like this happen, responsibility falls on both sides. Even if one had done all the things properly on one side, if the other side fails to do so it is your fault. If their etiquette was bad you should never have taken a guest there to be embarrassed. As host it is your job to know.
As a Chief Instructor, it would be a total embarrassment for me if one of my students was humiliated because of the actions of my dojo members.
One of the posters felt that the guest had indeed been treated very kindly... The problem here is that the guest was Japanese. What we think is appropriate, friendly, and kind can appear to be overly familiar, too informal, and disrespectful. It can very much depend on how "old school" the guest is and how used to the eccentric ways of Americans he is.
It must be part of a student's training to learn this stuff. It is a disservice to them not to because then they don't know how to behave when they are on their own. They can't go to Japan without causing embarrassment. They can't train with outside Japanese teachers without reflecting badly back on their own dojo or organization.
As Joe said, there are a lot of lessons to be learned here, by everyone. In Budo it's all about not having a "suki" or "opening". When something goes bad, there are no excuses. It is always your responsibility even if you think you didn't do anything wrong. It is your job to foresee issues and make sure you "close the openings".
This kind of thing ends up being embarrassing all around. That's why it's so important to know how to do things properly. The fact is, Japanese etiquette is so Byzantine that only they really get it (and folks like Peter Goldsbury or Phil Relnick who live there for decades). So if you make a creditable effort, they cut you all sorts of slack because they know you don't really get it.