1. Please don't assume nationality like this, it is xenophobic. Eastern European usually means Czech, Slovak, Polish, Croatian, Serbian, Macedonian, Romanian, Slovenian, and so on. I know "Russian" evokes this image of someone scary and illicit but there are way scarier types in Europe proper who are more likely to own a Rolex or adjacent expensive brand. We don't even know this guy exists.
2. The question is valid though, and I'm sure LE are well focused on connecting the dots in spite of telling the media they think Jay got 'lost'
I respect your personal experience, but we actually have no idea if Jay did drugs, what drugs he did or how he felt and have no choice but to take Q at face value until there is evidence to suggest otherwise. IMO he is very sus, but he doesn't need to lie about whether Jay was hungry or not. The lie would be that they have nothing to do with his disappearance if they indeed do. Everything else they have said could be 100% true and they could still have driven him to a cliff and shoved him over the edge.