If you are worried you could ring Axa and fax them Milo's full clinical history, ie his vet notes, they can tell you whether they would cover the eye problems.
When I switched Riley to them he had been treated for a foot infection due to falling off the towel rail and his 'heart problems' (aka panting after da bird!) had been investigated.
They replied in writing that 'the problem with Riley's foot appeared to be a local infection that responded to anti-biotics and therefore not pre-existing' .
...and re the panting ' I can confirm Riley has been treated for a respiratory problem and that the treating veterinary surgeon found no relation to any heart problems, it was stated that the heart was normal. If future claims for respiratory problems were made, your veterinary surgeon would have to substantiate that the two conditions were not related for the condition NOT to be classed as pre-existing'. I'm not worried about any future respiratory issues being excluded as I know that there is/was nothing wrong with him, he was just getting over-exicted about da bird!
So as per the above Milo's eye issues could go either way!