The remediation costs were in the six figures...There shouldn’t be anything illegal about doing work to the other party’s property with their consent.

So, while I think it's nice that you want to help them remedy what they seem to feel has become an untenable living situation, I certainly don't think you should also be required to foot any sort of financial bill to help solve their problem.Is Tenant B open to leaving? 

All we can do is know what the moratorium doesn't include and capitalize on those remedies.  

These are things that are very easily remedied and cost very little.

The deed of trust stated if borrower defaults on payment or tax or insurance , lender will foreclose as remedy.  

We are waiving the asbestos ($200), (possible asbestos containing vinyl in kitchen, which we will either cover up with vinyl plank, or remediate once we actually own the house, and lead ($300).

Curable remedy.  

For lead and windows, as pretty as that wavy glass is you have two issues, it will be a rental so you have to remediate lead to the level required in your state as a rental.

If you were buying a property in South Bend, presumably it could be subject to this, so might this be a contingency in a purchase contract to make sure it was already going to pass (or some concession was made to offset the cost of remediation)?

Side note, I hope it does not reach the summary process, but this tenant is particularly combative and has also blocked my number...The verbiage on the NTQ isANY SUMS OF MONEY TENDERED TO LANDLORD OR THEIR ATTORNEY AFTER THE DATE OF THIS NOTICE SHALL BE ACCEPTED AS PAYMENT FOR USE AND OCCUPANCY AND COSTS OF EVICTION ONLY, AND SHALL NOT BE CONSIDERED ACCEPTANCE OF RENT, NOR SHALL IT PREJUDICE OR PREVENT THE LANDLORD FROM PURSUING SUCH REMEDIES, INCLUDING EVICTION, TO WHICH IT MAY BE ENTITLED AT LAW OR IN EQUITY.Best, Michael