Well, since the last time whenever he played the match. His contribution level regarding through the club is nil. I mean, Mudryk didn't fulfill the purpose of the Chelsea team like for what they hired him for. Chelsea have Cole Palmer, whose contributions are unimaginable. So I think Chelsea won't have any concern piece. In the absence of Mudryk, there are many other players who can contribute much better than him. To be honest, Mudryk's career may be stuck in a difficult situation just like Pogba was. Because, as you described, he is 23 years old, and still he is affiliating with such kinds of illegal activities. So his involvement in similar issues at such a young age can ruin his career.
Losing Mudryk may not affect Chelsea's performance too much but as a football fan I am quite sad to see players who are caught using banned substances even though it is very detrimental to them and also the team I mean if he is absent then Chelsea still pays him a salary even though he does not contribution, just like Pogba's case where Juventus still pays him a salary even though he does not contribution, but also with this case the players will be more careful because if a scandal occurs it will ruin their careers.