BMW College Grad conundrum here

My Bro-in-law co-signed for me so I can get the college grad incentive, but dealer informed me that it got denied. They say its because he just leased using college grad 3 weeks ago, but I was under the impression you can do college grade multiple times as long as you’re within 24 months of graduating.

Now, I have my sister who got an associates about 18 months ago. Does she need to be in my household, or is my parents house(different than mine) okay?

I appreciate any insight, even if its anecdotal.