I forgot about that this weekend. I recalled they usually have a spring show and saw the dates last month - thought that may work for me to head out (I'm about 45 minutes away) but completely forgot until now. Reading your post, I don't feel too bad about missing it now
Sorry it turned out to be such a disappointment/waste of time. Any of the vendors speculate as to why? Definitely not a lot of local promotion (that I noticed anyway) - in fact, what I recall jogged my memory of that show was seeing one of the grading companies note it on their upcoming shows.