Dinklebot spawn rate question - Rare spawn missions

I have not had the rare spawn quest activate in my game at Sanctuary. I went to his location to try to get a Lucian’s call loot o gram but he did not spawn in about 12 or so save and quits. Do I need to first complete the quest to get him to spawn, or just bad luck?

Can you get rare spawn quest to appear just by saving and quitting in Sanctuary or are they timed with missions throughout the story?

I’d like to know as well. I’ve completed the normal story playthrough and never got the Kill Dinklebot quest.

I got him to spawn by just continuing to go at it. Never got the quest yet. Eventually got about 10 loot o grams but just white weapons.