the reason for `a` tags being kind:pubkey:dtag is they are parameterized replaceable, the d-tag is their "permanent" identifier for an event type that can be replaced, so its id is not a stable reference

because all of these events are this type, you just need to come up with a scheme for creating the d tags i think, they can be anything really, probably might even be better to make it a nice big thing like an identifier hash so you have no issues with collisions

i think that's what you are having trouble with, not sure