So, I finally got a hold of Dr. Silverman today at Avid. Even though the reports came back from Kansas State Univ. that the microchip caused the scar tissue growth, Avid is denying it and says they need to look into it further.
Dr. Siverman is suggesting that some other trauma to the shoulder or a vaccine has caused it. Merlot hasn't had a vaccine in his shoulder area, they are always given in his back leg. I think I would remember a trauma to the shoulder that would cause that much scar tissue.