I found this re Soros:
The estate of George Soros is located in Katonah, New York and is located on a sprawling estate. The Charles A Platt designed home is rumored to be decorated with many pieces of fine art, including pieces by Sargent and Cassatt. In 2003, he purchased the property from Jurassic Park author Michael Crichton for $21.5 million and with this purchase came 63 acres and a 19 room mansion.
Unless Soros owns another estate with 400 acres it's somebody else. We need to keep digging.
Thanks. My WAG was a miss it seems.