Nothing but scripted propaganda. I don’t think he even removed the poster or banner. They randomly pulled an American and held him to bargain for easing of sanctions. When they didn’t get the desired effect, they tortured him.
My opinion is they waterboarded or used some other form of water torture and went too far and caused a drowning event. That’s why MDs at UC Med center could not find evidence of physical trauma, let alone botulism poisoning.
In the end, Warbier blames the Obama administration for encouraging him to commit this crime. I can totally buy that. He was a child of the Obama era, and a do-know-wrong resistance millennial who’s generation voted for a communist Muslim as President twice.