The gift deed is not valid.
The landowner after making a joint development agreement has made the builder an interest holder in the land and hence the landowner can not encumber the proeprty by creating a third party interest in the same land.
In the JDA there must be mentioning of sch restrictions on the part of the land owner.
So the landowner must resolve the situation since the interest of the builder due the unlawful act of the developer is getting hampered.