So im part of a campaign ran by my friends. This campaign is in no way serious or RP heavy because its our dm's second time doing so. To give an example, my character was given the ability to speak every language in 5e but only when he's drunk. One of our friends had to quit due to school so we were looking for a new player. I invited one of my other friends who is a very experienced dm (L) looking to play for once. The dm made a house rule that when you role a nat20 on initiative that it doubles the number on the dice. (Ex if you roll a 5 its 10) Everything seemed fine at first but then I started noticing L's discomfort with the nat20 rule. After our latest session I got a text saying that our group doesn't follow the rules when it comes to dice roles and he's about to leave if they don't fix it. From what I've seen playing dnd, every game is different. The books are there for guidelines, thats what great about dnd. I dont want him to quit because our group won't have enough to go on. I need some advice on how I can fix this. Thank yall.