Hmm... it sounds to me as if they are saying the same things human herbalists say about the same herbs and much of THAT is untested in humans let alone parrots. Oh well.
Yeah, I'm a scientist by training (astronomer) and I am big on data over anecdote. A favorite quote of mine is "The plural of anecdote is not proof". (Penn Teller of all folks). Anecdotal evidence IMO provides hints of where to dig, but it is anybody's guess if any given biased observation is accurate or represents a common occurrence, so it's a worrisome way to make life or death decisions.