There should be an optional quest featuring HR Kirin, though I'm not sure if you need to unlock it (and how). It's 8* like the other optional elder dragons; have you done those quests?
Edit: I just remembered. You get the quest from one of the researchers in Astera, near the big tree. I believe the old, impatient wyverian at the table. So you may need to clear their other quests first for it to become available, much like LR Kirin required you to catch a handful of monsters for that biologist.
Yeah, it's probably the case. Had made a second character that I'm using now(and probably will stick with), so couldn't be bothered doing most of the sidequests again, just wanted to hit late game as fast as possible. Was farming up a third armor set for HBG, but probably should just knock out the side quests.