There’s no need to have the other user go through a new Bluetooth pairing procedure since a dog profile can be “shared”.
From the FitBark mobile app:
Click on the name of your dog on his home screen (top center)
In the dog Menu, select “Manage Users”, then “Add User”
Insert the email address of the user whom you’d like to invite
Select whether the user you are inviting is an owner, a follower or a veterinarian
Select “Send” to send the email invite