My dog was attacked and bitten by another dog during her stay. She required medical care. Guess who paid the veterinary bill? The other dog owner who attacked my dog? No. The person taking care of my dog? No. I had to pay it. Why does the victim have to pay for the damages done to them?
No one is blaming the victim. Rover's insurance coverage is a secondary form of insurance, in which you get reimbursed for your out-of-pocket expenses. I've known doctors who have required payment up front and I would receive payment from the insurance company. This is merely how some insurance works. It is a shame that the owner of the other dog didn't take responsibility and offer to pay, but you are covered by Rover.
Call the customer support number [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]. Your situation is exactly why they provide insurance protection. Yes, you have to pay out of pocket but Rover should reimburse you. Keep all your receipts.
When I spoke to Rover they told me that their terms of service states I have to pay up to 250 dollars of my own money (the deductible) before the insurance they provide starts. It does not matter that neither my dog or I were responsible. They also said it was not reimbursable