Save from being foreclosed on....need help

my house was being foreclose on and I was able to save it. From a buyer who bought it and rent it back to my mom under the option lease to own. No I am so thankful to this person. We have a three contract and a 3 percent credit towards the repurchase. Now I was told I am not able to buy it back but my mom can. Now the buyers is asking my mom to refinance the house within a year instead of the three years. But they are advising us she would do a refinancing taking over the loan in her name instead of a new sale. Since the house is already least to her with the option to buy. I have been searching the internet to find this kind of loan refinance but I am unsucessful. I need help if anyone is familiar with this or any advise. Thank much.