Resolved Question: Ex Husband Died, Ownership Of Property Issues Now In Question.?

Ok this question is for my mother. She was married to a man for 7 years, about 4 years ago. While they was married they bought property and a house together. He was very abusive and had a alcohol problem. She filed for divorce but the judge rested in his favor and she lost everything, even her half of the estate. About 6 months later they tried to work things out. They was doing good, and both agreed to write up a notorized contract on the ownership of the house. Pretty much stateing that he was to put her name back on the deed as soon as possible and if at anytime, one of them was to pass away in the future, the other would then become sol owner of the property. Well things went south and he started becoming abusive yet again. She left him. Now here it is about 3 1/2 years later and we find out he has died. He never got around to putting her name on the deed like the contract requested. Then his ex step sons from his first marriage come out of the wood work to try and take over his property. They claim they have all this legal paperwork stating the deed was in the deciesed’s name and no one elses ect ect. Well my mother still has the notorized contract he signed that clearly states she is to become sol owner after his death; weather he got around to puttting her name on the deed or not… bottom line is, he was suppost to. She talked to afew attorneys and they said her contract will over ride ANY will (we don’t know if he even had one) and also ex step sons have no rights to sell, rent, lease ect until/if it goes though probate. So what now? Does my mother have a fighting chance to reclaim the properity that is rightfully hers? Can she avoid probate? What if no one puts it into probate? Will the state eventually take it over and sell it for back taxes? Please any advice would be helpful!