Brian I am sorry to say you are misreadiing that clause. The AXA policy definitely will NOT cover ANY pre-existing conditions AT ALL, OR conditions which appear in the first 14 days of cover.
The very best of luck on Izzie's visit, Amanda. I think unfrotunaely you are almost certainly looking at SM and probably will really want to get a referral to a neurologist and in the meantime, I hope you vet might get Dr Clare Rusbridge's treatment protocol and immediately get Izzie onto pain relief. There are links here on the board or you can download it and print it off her website.
Please let us know how things go.