I just read through this whole thread. Unfortunately I can't see the pictures here at work. I mainly read through it for your experience w/ sani-tred. I spend a lot of time on a pond board and a fellow there had the same type of experience. The tactic the sales rep used is exactly the same. He called the user a liar and claimed improper technique in application. No sani-tred for me...ever.
However, everyone that I've seen post about pond armor and Butch has nothing but good things to say about them.
Good luck,
Steve.