Jammer, You were thrown into unfamiliar territory and caught off-guard by the phone call. Everything after that is water under the bridge. Hopefully, the MSP can get the shop rescheduled, and give you instructions on what to do with the kit.
Going forward, don't feel pressured when a scheduler calls. They need help, now. Maybe it can be mutually advantageous, maybe not. If you don't want the shop, explain that there's no room in your schedule for it and thank them for the opportunity. If you want the shop, by all means, ask for details to make sure. Sometimes the scheduler will offer a bonus right off the bat, but not always. If timing or mileage is a factor, and a bonus is not offered, ask. Took me a few times before I got comfortable doing that. It's either do-able or not, for both MSP and shopper. If you and the MSP agree, ask the scheduler to send you an email with details.
It seems to me that deactivating is a bit hasty, and maybe just a preemptive strike. I wouldn't sever ties this early in the game. Hang in there!