So, after the Giths kill the other guys on the bridge, they all disappear, however the questmarker for the gith patrol remains. Am I missing anything here? Should there either be giths in the spot or should the marker have disappeared?
After the cutscene there should be Githyanki on the bridge. And a red dragon. Then once you join them down there one of the gnarliest fights in EA starts.
If you manage to pass the skill checks in the conversation (including Lae'zal passing a... charisma saving throw I think?) then you don't have to fight them. I believe when the game releases the quest will continue, but for now it is a dead end.