Not too sure if you'll see this but I believe there is one way to cheese crota. I've only been told about it by someone on lfg but I think it's the party leader leaving and during that bit of time while the game catches up to everything warlocks with solar wind go out and hit crota but he doesn't move. After the game catches up, he gets all that knock back during the time period. Idk if you guys knew about it but better safe than sorry.