It's not unreasonable to think it possible.
Yes, and the researchers/scientists are quoted saying as much in the article
75The Scythians then take the seed of this hemp and creep under the felt coverings, and then they throw the seed upon the stones which have been heated red-hot: and it burns like incense and produces a vapour so thick that no vapour-bath in Hellas would surpass it: and the Scythians being delighted with the vapour-bath howl like wolves.[72] This is to them instead of washing, for in fact they do not wash their bodies at all in water.”
Herodotus.
— Now Herodotus is not exactly a reliable historian, but I don’t think there is any reason for him to have just invented this.
Also, “medicinal” use wasn’t really a category that they would have recognized, nor was there a taboo on intoxication that would make them invent such a category. There might have been ritual element to it, or some other instrumental reason behind it, but I think a contemporaneous description of them seeming to enjoy it is pretty good reason to believe that part of it was that it was just a good time.
"Chemical analysis of braids of hair from the bodies of several people found in the central burial chamber identified chemical signatures consistent with THC"