We will be camping for a week and taking our dog with us. We would like to do a day trip in which the dog can not go and we don't want to leave her in the camper all day. Can I use Rover for a day without meeting the sitter prior?
That's certainly possible. Contact a few sitters in the area and tell them what you need. For daycare or a longer all-day boarding situation, they may be able to accommodate your needs.
I've accepted a couple of out-of-town dogs without M&Gs because their owners were attending a function and couldn't bring the dog. It all went well in the end, but you never know. For a stay that was less than a day, I thought I could risk it.