If it has enough travel across the hub, ie it will reach first gear, then I don't see any reason why it wouldn't work with Ergo shifters: the indexing is in the shifter, not the mech.
Even though you have three different generations spanning ten years, it's only the RD that might be incompatible.
Yeah, that's a 1st gen 7 speed Athena RD.
If it has enough travel across the hub, ie it will reach first gear, then I don't see any reason why it wouldn't work with Ergo shifters: the indexing is in the shifter, not the mech.
Even though you have three different generations spanning ten years, it's only the RD that might be incompatible.