@Verna Medlin "So now what does wife do when she can't afford to hire a lawyer to straighten out the mess?".
There are answers here from people much, much more experienced than I, so take anything I say with a grain (or several) of salt.
I see a few options:
1) Check with the local DA on your options for pursuing your ex for fraud. What you've described, not a lawyer so just opinion, sounds like fraud. Check with several attorneys, including the local DA's office. There may be resources for you, legal aid, etc. Personally I would do this first regardless of my next move. I would also ask the DA, hypothetically of course, what would happen if I then did option 2 or 3 and the ramifications of such.
2) Nothing. Keep getting the rent checks from the "property manager". (Personally, this is not a route I would take, but everyone is different and sometimes the stress of dealing with something isn't worth the financial return)
3) Contact the other injured party in this nightmare, the "tenant" that is being sold your house. They may have entered the purchase agreement in good faith, not realizing they are being defrauded. There are a lot of youtube influencers that make these scenario's sound like they are perfectly normal, even though they verge on, or are, outright fraud. The "tenant" may have more resources to pursue a fraud charge. Remember that they are, at least it's likely, a victim in this too. How would you feel in their shoes? They think they are buying a house only to find out the person selling them the house isn't actually the owner. Use verbal judo to help the tenant see that you both are victims. Use statements that identify with them, "Yes, I am also angry at "PM/Ex/etc"! I really can't believe they did this to you! I know, right, we've really been defrauded!". This can help redirect their anger away from you, to the person(s) that committed fraud, and get them to identify with you, ie, "We need to resolve this" vs them thinking "You're trying to take my house". You want them, by the end of the conversation to realize you are an ally working against the one's that defrauded you both. (I worked in customer service previously, verbal judo is a required skill IMO)
4) Go nuclear. Evict the "tenant". If they claim to have ownership advise them that they are the victim of fraud and that the house is legally yours. Ask to see any paperwork that has your name, the one you've stated is on the deed, on the contract. If you've already attempted option 3, this shouldn't be a surprise to them. Let them know that you are very sorry that they are a victim of fraud and that you will be glad to do anything in your power to assist them in legal restitution, but you are not the one that defrauded them. This will likely kick of a flurry of lawsuits, so expect that. (This is the route I would take, push the problem back to the one's that created it in the first place. That said, this route is likely to be time and energy consuming as well as stressful.)
Just my thoughts. The idea being that if you can't find an attorney that will help without money out of pocket you can't afford, then move to recover your house and let the other victims respond.
I would talk with an attorney first, because I don't really see a scenario where you're not going to need an attorney. (maybe option 2) Whether you initiate a lawsuit, or move to evict and then are sued, you're likely to end up in court.
I really feel for you in this. It sucks when other's actions impact our financial well being. Keep in mind you are not the only victim here, the current "tenant/homebuyer" is also a victim.