How to confirm previous owner??

I am looking at purchasing a Gen 2 A6 TDI. The vehicle was a 1-owner lease and turned back into the dealer a couple weeks ago. How can I confirm if the previous leaser claimed any of the emission fix money? I put the VIN through Audi claims portal and it claims that $8,400 is eligible to the owner. If the previous owner claimed anything would it have shown the $4,200 or something available?

Thanks

How to confirm previous owner??