Considering that Bungie has said that knocking the bosses off the edges of the area is an expliot and will be fixed, eventually teams that only glitch bosses and don't know how to properly deal with them won't be able to clear. If it was up to me it would be a simple fix, if he left the platform insta-raid wipe. Soon fix the glitching issue. The terms and conditions are quite clear and you should report all the members that you went raiding with.