Is MoU(Unregistered) legal in court? Which is having a stay from High court on property

I made saledeed(Registered) for 91sq yds(Amount settled46L) out of 103. 12 sq yds (having two mulgies), which is having a stay order from the High Court that the property should not be alinate or a third party shouldn't enjoy it. I took Sign from a seller (uneducated) in MoU (unregistered) that rents should get to me until the case closes and after register of two mulgies the remaining sale consideration amount of two mulgies i will pay you, without knowing their legal heirs. After their father's demise, immediately i took sign from their heirs on undertaking, by telling them that your father agreed me to sell that remaining property after the case close in High court, so just taking sign that you should not sell to any one, without mentioning the MoU details which i made with their father, Later they got to know about the rents which I'm collecting, told them that i will return it back, they asking me continuously, then i told them about MoU. Later their children sent a self notice to cancel the MoU i have not agreed, then they sent me legal notice, i have replied them, that land belongs to me, we are owners., and i made false complaint on their legal heirs that they threaten me and my wife, even with the tenants of 2 mulgies i have took false complaint on their legal heirs. Then they filed a case against me, claiming that 12 sq yds belong to them and rents should go to them, & the rent that is collected by me should return to them. The 12 Sq yds property is in their name only, electricity bill is coming with the legal heirs father's name. Will i need to hand over their property? Presently case is going on civil court, what is the chance to them of winning the case.