just that they died while under the influence
We don't even know that since cannabis can linger in the system for over a week after getting high. It's very hard to objectively test if someone is actively under it's influence, best we have is watching for behaviours that could easily be caused by any number of other factors.
I'm confused, how will this accomplish anything if he's in Germany? Is this just an intimidation tactic? Or do they think they can successfully drag him to Russia?