I would like to be able to disable the gravestone mod for specific players who want a more vanilla death experience.
I have looked at the example configuration and I could not find any way to accomplish this.

If it isn't already a feature, perhaps an in-game command to configure this behaviour would be suitable?

There is an in game command: /yigd whitelist. By default it's a blacklist, so you can add whatever person you want with that. You can also toggle it into an actual whitelist

Oh nice! I think I must've misread what the command meant