What are the names of the 2 or 3 sitters we have used in the past?

This is not the place to communicate with the Rover Customer Support staff. You can webmail them here:

https://support.rover.com/hc/en-us/re...

or call them at [Edit: Rover’s contact options have changed. Visit the Rover Help Center at https://support.rover.com/ to find the phone number, help articles, or chat with the team]

Or you can just go to your Inbox and look under the tab Past Stays:

https://www.rover.com/account/inbox/p...