Haven't seen anything official yet but both Jorma and Marty have said that Signe Anderson passed away on the same day as Paul Kantner. Amazing coincidence right?
btw, that farewell show was recorded by Ray Anderson, brother of Signe's husband Jerry. Ray had been doing light shows at the Matrix as the Holy See. He was all over the scene at that time, saw the Elevators at the Avalon, took photos of the Great Society in the studio, etc. In the 1990s Ray opened the Grooves record store in San Francisco.