The Shay did not go to the Silverton. It was still on the roster at the end of operations and was transferred to the Morse Bros. Machinery & Supply Company. I do not know its disposition after that.
source: "The Switzerland Trail of America" by Forrest Crossen.
Note: The only Shay on the Silverton was the one that Otto Mears bought new on one of his trips "back east". It didn't work out and he traded it to the Rio Grande Southern for a class 56 rod engine. There doesn't seem to be any evidence that the RGS actually used it. It was sold and ended up on a number of logging roads until it was scrapped sometime in the '20s.
Regards,
Donald Foster