This is a cool idea! The only thing is that they seem to be very self sufficient and there might not be very much demand for them. The other DoL exist specifically to gather crafting materials for DoH. While they can get other odds and ends (minions and the like) their main focus is to supply the crafters.

Scavenger/Archaeologist wouldn't have this benefit, and I don't know if they'd make a class that purely exists to gather unique items. Maybe if they also added a DoH class that worked with bones or stone? Boneworker or Mason (maybe these two can be combined into one crafter class as well, since it seems their options would be limited otherwise).

Regardless, I still think it's really cool. Perhaps they can be really heavy on the lore as well and can also discover new things about ancient civilizations that no one else could.

Also! There's a group of these in the South Shroud investigating Gelmorra's ruins. Perhaps quests could involve them.