User blog comment:DeltaHorizon020/PE Proposal: Mr. Widemouth/@comment-14660436-20200104164431

Arguing about the legitimacy of the work aside, I'll go with a yes. The graveyard full of children confirms his status as a prolific serial killer and reveals that he has a substantial body count. Since there's no one else to compare him to in-universe, there's no real reason for him to not count.