I’m wondering the same. I have the HK Citation 200 and haven’t found a way to make it work with Home Assistant.
The only proof that it’s possible that I have found is from cristianm.bunte in his comment here: A different take on designing a Lovelace UI - #5148 by cristianm.bunte
In it it refers to media_player.hk_citation_one_d20393
So @cristianm.bunte , if you see this, how’s your setup to get your citation one connected to HA?