The relationship between the mountain pine beetle and fire is still an ongoing area of study. The history of fire suppression is one of the factors that led to the mountain pine beetle outbreak in the first place. Now that there are all these standing dead trees, there are some who hypothesize that it could contribute to more forest fires or more intense forest fires.
It's an ongoing area of study to look at their relationship, but the mountain pine beetle could be one of the contributing factors to the recent forest fires we've seen.