HELP! Legal question on specific performance

[Leslie Lovelace]

We had an active purchase contract on our home with buyers who were paying cash ($495k). However the night prior to closing, my siblings placed a memorandum of interest on our home. (Another long story). They indeed had no interest in our home. 

We did sign an extension to close, but the memorandum was not removed. The buyers requested that we sign another extension, and we decided not to do so. We have asked the buyers to sign a Mutual Release and they will not. The memorandum of interest was removed now, and the purchase could go through, however we have decided to stay in our home at this point. 

The contract expired on December 13th, we we would not sign another extension. Now, they are saying that they want to extend again until January 20th, 2020. 

We are in Kentucky, and our purchase contract does not state specific performance or any other remedy. So my question is, can the buyers sue for specific performance now that the purchase could go through even though the contract expired and we would not sign an addendum to extend a closing? Also, if so, how likely is a judge to force us to sell? And how lengthy of a process is this?

Any help and adobe are greatly appreciated!