Re #3, while the pianist sounds like Tristano, I think it unlikely to be him - the solos, although similar in style, seem to display a slight lack of surety/ confidence that Tristano never did - listen to his (LT) solos on the Capitol session, recorded in January 1949, for example. The pianist is probably one of his students of the time (late 40's early 50's), such as Lloyd Lifton or Sal Mosca. The same reasoning could be applied to the tenor, although I have no idea who else of the school apart from Marsh it could be. The trumpet could be early Don Ferrara - he was studying with LT from about 1947...