My understanding based on your response:Old debt $140k - stays the same, $70k on each side.New additional debt $110k (is this applied to the Duplex, the property that secures the debt, or new SFR, the property the debt is used to fund?)

As a creditor's representative in bankruptcy I bumped into a stripping tactic, it didn't fair well for the debtor.

If you are correct then he can still get the judgement and have a collection agency buy the debt or attempt to collect more money by sending him to a collection agency for a fee. 

Lawyers for the debtor will try every kind of legal theory to delay, cancel and repudiate the debt.

That's why usually the IRS auction states "only the right, title an interest of he debtor...".

Is there a medical debt or student debt holding down the score?

Once you get a judgement you can hire a collection company but they just trash credit.You can also get an attorney but they are a waste of money.They will just do what I am about to tell you.You can either spend a bunch of time collecting yourself OR you can sell your judgement to a judgement recovery company.If you sell outright to them you might get 20 cents on the dollar NOW.It depends on when they do the research if the judgement company feels they will recover anything or it will be a lost cause (debtor filed BK etc. or has a job that is not garnish able).You can also have the judgement company pay for court costs to collect and garnish but they will split profit with you 50/50.Judgement companies will tell you it takes sometimes 2 to 3 years to recover a significant portion of the judgement.You might be better off asking the former tenant what is the most amount they can pay TODAY to settle the debt??

You can report debtors and it does get reported on their credit.

In a judicial foreclosure state the lien holder foreclosing must first sue the debtor in court and obtain a judgement.

Foreclosure or reinstatement of the loan/debtor.