—”It seems odd to me that an OEM dealership selling recent used cars would have a fly by night financing firm”
Depending on your credit rating, they will “guide” you to their lender of choice.
Guessing they have several to show you.
Also, the “dealer” could be a subcontractor that specializes in subprime borrowers.
Doing a quick web search it appears the lending company is a subprime lender.