Stone citadel boss health is bugged

Me and my 2 teammates did 20 million damage and his health bar went down 1/150 which means his health was possibly at 300+ million . Lmao come on guys that’s ridiculous when the strongest hit from my warrior does 150k-250k. Could be a bug with teammates joining and bosses health gets all ramped up too much. Please just fix the issue and stop having some of these bosses have half a billion health bar. Makes the game soooo boring and sooo annoying to go through. Meanwhile he’s also got multiple one shot mechanics against my friends not play warrior LOL. this isn’t a single player game so stop making group play so un enjoyable