Fred, I believe the "wizard sleeze" is a 100% new frame, not a hard tail weld on.
That being said, if you have a frame you like, but the business has questionable practices or other things I find undesirable, is it worth the risk to spend the money with them?
Plenty of reputable frame builders are glad to publish their information so their customers have all of the answers needed to make an educated decision on their products. If any shop says they won't because they're concerned about someone stealing their intellectual property it's absolute BS. I can almost guarantee anyone that would actually want to copy a frame won't achieve anywhere near the quality as the original.
And just my personal opinion. If I was looking for a frame to be built, I'd probably like the shop bike from the company to be built on something they're selling, not just a 4 ft long swingarm and a silly exhaust.