If they don't want to lump the towers and Coil together, they could just call it "Duty Roulette: 24 Player Raids" or "Duty Roulette: Alliance Raids" or something similar. "Towers" would become an obsolete name if the intent is to lump Void Ark and the related raid content into it eventually. (Also, let's be fair: Only one of the original three raids was even a proper tower. People just called them all that because of the questline.)