Rocky has developed Diabetes. I will need sitters who can administer insulin shots?

You need to call Rover Customer Support 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 look through the profiles of sitters in your area for ones who are or have been vet techs. No one here can help you.

As Karen says above. Also, they won't give you a list of names either. When searching in a forum or reddit etc, sharing your location is your best option. Rover will not give you a list of names of their sitters in the entire USA. That's not how it works. If there's a sitter here who can administer shots (for example I can), it won't be very helpful if i am on your "list" if you don't live in Colorado. Just something to remember for next time, as it will make your search much easier.