If parties are talking, that indicates an intent that a deal...

If parties are talking, that indicates an intent that a deal will be struck. A court will make a decision when it believes negotiation and mediation has come to an impasse. The decision would be based on president comparable sale contracts. (on a $km2)
If the land owner turns around and says...."well I now don't want to sell" he/she can be sued for misleading BND, and potentially to the NPV of the project.
You can not blame a landowner for negotiating hard and getting the best price he can. But it is not unusual a handshake is found on the steps of the court house on the day of the first hearing, as who really likes lawyer fees.