I am not entirely sure if Chelsea would even care, Mudryk isn't really a must for them, they are winning without him easily, so it doesn't feel like they would care. They famously have a lot of players anyways, that was a talk during the summer, they have like 40+ players or something, probably less now but still a lot, so losing one of them won't matter.
If this was Cole Palmer or Jackson then we would be seeing them in shambles without a doubt, but Mudryk doesn't really feel like he is important enough to care. They would just use that as a reason to unload him and sell him to another team, that has to be the most important part. I believe we are going to end up with a lot more and that has to change on the long run.
Yes, Chelsea doesn't seem to be too bothered by the problems that befell Mudryk, especially since his contribution to The Blues is still lacking, his performance does not reflect his price, so losing him will not affect Chelsea's current performance at all.
However, if Palmer is in that situation, it will indeed be a big loss for Chelsea because he currently plays a big role in every victory achieved by Chelsea.
It seems that if Mudryk really uses doping, we will see another Pogba.