It's highly unlikely that it was secured property. You may well be "judgment proof" and immune to just about anything that the creditor can do, or you may have to file bankruptcy. You may wish to visit with a bankruptcy attorney - bring all the receipts and paperwork concerning these purchases and all the suit proceedings.
You should take a look at taking them to small claims, and ask for the funds back. The company may just crater and pay it. If they answer, you can then go get an attorney, and claim attorney fees too, which can be awarded and go over the usual $10k limit.
I'd write a certified letter to the hospital and demand the funds back, or their justification for their action. If the hospital does not respond, then take it to the small claims court nearest to it. This won't cost much. and you'll at least get an answer.
Sue him for fraud. If someone is attempting to use these documents against you in some way, you'll want to sue for a declaratory action that their claim is not valid. But first let them know that you are claiming that the documents have been forged. That company will be MUCH more likely to let it go if are suing the title company and its vice president. You can even ask that organization to join you as plaintiffs.
When you file bankruptcy, you have to decide whether you will keep your house, or not. If not, then the debt will usually go away too. If you want to keep the house, you will typically have to pay for it.
Best thing to do is get a consultation and let someone look at the paperwork. I don't know why you'd have tax returns going to pay a mortgage. Happy to look at it and figure out what the best route is. It is not necessarily bankruptcy.
You need more than a DBA, which is short for "doing business as", typically indicating that you are just doing business as yourself under another name. If you are going to be in business, you need to establish a business entity that will provide some legal protection. Usually we're talking about an LLC (limited liability company) for a business as you describe. Of course, the details matter, and you ought to talk more specifically with a local attorney before making a final decision.