Background checks sound pretty sleazy in any case - what business is it of yours if someone once had financial problems (such a record will never tell you the why only the what).

Call the last employer but one for an honest assessment of the reasons your prospective employee left and how easy they are to get one with - you already know they have the knowledge required for the job - you tested for that before and during the interviews - right?

If you still feel a little uneasy then it's a "No Hire" - end of story.