Owner summoned by local court now says that he did not give that GPA

Bought plot in 1997 from mumbai based realtor thru GPA by registered sale deed. Was Validiation GPA Registered locally in absence of owner. In 2013, local goons created another sale deed, claiming ownership, assisted by mumbai owner. Criminal and Civil case filed, interim injunction obtained. Owner summoned by local court, now says that he did not give that GPA. We only have photocopy of GPA. RTI query to registration office says GPA not traceable. We had boundary wall and room since beginning and recently in 2015 took Electricity metre and house number from panchyat. advise further