I'm not sure where you heard that, but following the Jonestown mass suicide, the attorney of Jim Jones' religious movement stated Jones was to leave all his property to the CPUSA (Communist Party USA), not the Communist Party of the Soviet Union. This request can be found in Police Files: The Spokane Experience 1853-1995, which is written by a career staffer (M. Kienholz - page 156).

The full request Jim Jones made is that, if none of his family survived the mass suicide, that all his property were to be given to the CPUSA. But in fact, three of his children did survive, which caused them to inherit the money.

However, if none of his family had survived, it is unlikely the money would have gone to the CPUSA, as a local news report notes his will was neither notorized nor witnessed. However, the law states that if no legitimate will is in place, the estate goes to the surviving children. So you could say in the end, his will was honored, but only because the U.S. law and his will sought similar ends.