If you read a few posts down, you will see that Fluffy mentions the possibility of Trey being at the club that night in advance, so I would say that the possibilities are good. One review I saw mentioned a Peter Gabriel cover, and Tim has been playing "Red Rain" during his sets this tour, so again that would be my educated guess that Trey did indeed join TR during the encore for Red Rain.
Trey did indeed sit-in for one song with TR in Winooski. He joined TR for Red Rain, the encore. I am pretty sure it was recorded on vid by Erich. I will give more details of the evening when I have TIMe. It's been a very hectic day.
Peace & Keep the Faith Fluffy "THE MUSIC BUSINESS IS A CRUEL AND SHALLOW MONEY TRENCH-- A LONG PLASTIC HALLWAY WHERE THIEVES AND PIMPS RUN FREE AND GOOD MEN DIE LIKE DOGS. THERE'S ALSO A NEGATIVE SIDE..." -Hunter S. Thompson