Difficult to know what to make of this.
On one hand there's no indication he had a prescription for cannabis and so was attempting to break the law in seeking it for fun use and getting onto any altercation with a dispensary is totally dumb and arrest is entirely defensible.
The car but of the story is very odd - on one hand he says he had the owner's permission to drive it but then, because he was drugged at the time wasn't aware of anything.
None of this seems to hold water and looks like typical Daily Mail rabble-rousing.
Then his Mum's bit on the GFM page further embroiders the tale of woe with your even mentioning the original altercation he started with the dispensary which cause the original address.
On the other hand, IF his story of captivity is true at all (and how can it be if, as he says, he was hallucinating) the Police concerned ought to be in big trouble.
in my view - based on what is reported - this little angel is not telling the entire story and giving it plenty of "poor me".