So long as he made a couple of speeches at the company's behest...and was depicted on their website without permission...he had a plausible denial of "association".
However, speaking as an ex-ad guy, once he makes an infomercial and endorses the product, he is inescapably involved in an "association".
Somewhere, there is a contract spelling out the terms of this association.
I have wondered if due to the claims he made of his prostate cancer disappearing etc. if liability could possibly attach due to his being a medical doctor of some repute. Found out he also made an hour long PBS special for Mannatech and gives them credit for funding his endowment chair at Johns Hopkins.
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