There is no cemetery, but they have a wall of remembrance, dog tags & various last messages. They work directly with the government, granting lawful protections, commissions directly from nobility as a fantastic business opportunity, and has some government backing allowing guaranteed income for taking some of the jobs. Connections.
They have monster activity data and although won't remember each person who commissioned some goblins to come through, they can recount number of orc subjugations or wyvern subjugations. There's datasets for migratory species, and they'd record significant, data-worthy commissions.