If the wife never signed any kind of loan/mortgage agreement, which it would seem she didn't.....then no, she has no obligation for the mtg whatsoever.

@Chris Martin  so many of these BP posts are like Paul Harvey's  "rest of the story"  its like pulling teeth to get to the bottom of these deals. this in my mind would be a quick flip or an owner occ... deal. 

If it is an REO, there is no longer a mtg, and the Former owners have no say so or rights whatsoever, the bank simply owns it.  

Do I simply call the tenants directly (it was like pulling teeth to even get contact info) and tell them not to pay those guys anymore?

they should be able to flush toilet, brush their teeth. showering maybe a problem.  

I wouldn't read anything whatsoever into numbers on a single unit taking a few more calls than normal to get occupancy.

I put the renters through a screening process and there have been minimal hiccups and no damage to the home whatsoever.  

I am not qualified to be a mentor whatsoever, but if you are looking to partner on some deals, let me know.

I do not have the money whatsoever to purchase this apartment.

@Daniel Rehner.If it's pretty obvious they can't afford it.. and even more obvious you don't need to deal with their drama, and you will be pulling teeth for rent, I'd look into alternatives.