A proper lawfag might give you a better opinion, but like, the synthesis path isn't a secret, there are papers describing it and it's public information.
Provided the precursors aren't themselves illegal to sell (which I don't know where they are at), I imagine things get murky.
It certainly seems like some sort of reckless neglect to advise an amateur to perform a sensitive reaction that should be pharmaceutical grade, and you certainly don't see, say, chemistry youtubers doing that sort of thing without big legal disclaimers; and they don't sell you the kit you need to perform the reaction.
If your kid went and got a blood clot over injecting tit juice with cat hair particulate and spores and shit, I mean yeah the people going “you should absolutely do this even if you're not a trained professional in a well equipped lab” would probably be co-responsible. Then again you'd be too.