AFAIK, that substance was found on his supplements, and that doping wasn't intentional, at least that's what WBC is saying. Maybe it got mixed with his supplements? Who knows. 

That substance (Ostarine) was on the World Anti-Doping Agency (WADA) banned list. A quick Google search shows that it increases body mass and helps maintain it even during a calorie deficit. It also helps improve bone density. So, yes, it has beneficial effects on those who take it and might alter the course of the fight. But, since the dosage was small (per the recent reports), my guess is that it won't affect the upcoming fight between these two.