Caudecus is introduced in the core story and in the Queensdale map and then again in the Caudecus Manor dungeon. He is not introduced via LS1. So yes, you you should absolutely know who Caudecus is unless you skipped the early - still available - content However, the Bloodstones and the White Mantle are significant parts of Guild Wars 1, so yes apart from some titbits in core maps, it is likely many newer players to the franchise will be confused here OH?! Do people do dungeons while leveling? I had always chalked that up to a far too time expensive side quest. That's too bad they're relying on you doing a heart in queensdale or an optional dungeon to know what is going on.