Curate, connect, and discover
I wonder if Michael Shelley got a grave. I don't think Gertrude would have made one; she's not sentimental enough for it. If you make graves for people you lose, you might think too hard about sacrificing them. If he had living family, they probably would have been at least a little estranged by virtue of how much time he spent at this job that, frankly, would make him sound like a lunatic to most people. I also doubt Gertrude would report his death in any official way. He would just disappear, never to be heard from again. Anyone else might not know he was gone for months.
The other assistants... they would know he was gone. Some silent acknowledgment that he wouldn't come back and shouldn't be spoken about. Maybe one of them would give him a grave, maybe. Or maybe not; after all, burials generally involve digging in the dirt, and they all knew about the Coffin by then. Who would want to tempt fate that way, and all for one dead man that cared too much?
No, his only grave is a labyrinth of doors. And even that twisted, painful testament to who he was and what he did, is taken from him when Helen usurps him.