Complex sentence: In the United States, though none of the revenue generated from Tough Mudder admissions sales goes directly to any charity, participants are incentivized by the Tough Mudder organization to raise money through their participation in a Tough Mudder event for donation to the Wounded Warrior Project.
Split into simpler sentences: In the United States, none of the revenue generated from Tough Mudder admissions sales goes directly to any charity. However, participants are incentivized by the Tough Mudder organization to raise money through their participation in a Tough Mudder event for donation to the Wounded Warrior Project.