Glad you're sorted. Unfortunately our experience is the complete opposite. We'd banked with Nationwide for years and did have the travel insurance which, when it works, is brilliant.
But
In 2018 DH, who was 74 at the time, suffered a very mild stroke. He had/has no lasting symptoms, takes no medication and was discharged from the hospital with no need for any follow up. He was not admitted to hospital, just treated in A&E. However, the advice was to mention it to our insurance company. Nationwide's response? We won't cover you for a stroke and whilst we are at it, we will no longer cover you for your diabetes and High blood pressure - all of which they had previously covered us for. So basically they refused to cover him for any of his previously noted conditions !!!
Fortunately we found a company that accepted us, no questions asked (including medical ones!) and this year's annual insurance, including the States and the Caribbean is £450 for the two of us.