Violinist Akemi Takayama is negotiating with Ehrlich separately, the paper says.
Ehrlich sued his fellow musicians in 2000 after they ejected him from the group. A Pennsylvania court eventually ruled in his favor and awarded him a share of the estimated worth of the quartet.
Shaw and Lederer, who are married, have declared bankruptcy and given up all of their assets, including their home. They have sought to retain their instruments or come to an agreement that allows them to continue to use them pending appeals in the Pennsylvania case.