What is tauck tours and what do they offer?

Tauck partners with Aon for Travel Insurance. We bought this insurance through Tauck specifically to cover us in case of a positive test for Covid and could not go on the cruise. Three days before the trip, one of us tested positive with very mild symptoms. We contacted Tauck and they agreed to refund 1/2 of the tour cost and the insurance would pay for the other half. When we called the insurance they said they required a PCF test. The test was taken and came back positive. Two months later they denied the claim because we didn’t go to a doctor. That was not necessary or practical. We had proof of Covid. Tauck is not willing to help. This was the insurance they recommended and sold to customers. We have now read many reviews of terrible service from Aon. Why is Tauck a partner to this company and not willing to help their clients. BEWARE. Terrible customer service.