Welcome to the forum.
Sorry you're having problems with your extended warranty company but if you care to use the search feature of our forum you'll find it's not all that unusual for many EW companies to look for reasons to decline a claim.
Did you buy the policy from CW? Have you dealt directly with the EW company? Have you asked them what maintenance records they need and why they need them? Is there required maintenance on an Auqa Hot system?
I think I would be in the face of the salesperson who sold me the policy... especially if you bought it at CW. I'm sure they promised something like "bumper to bumper, worry free" travel.
We've had our EW policy for >5 years now and have been very happy with them but we were lucky to get a good company.
Best of luck.