Very interesting - hope the original poster has fully recovered.
In terms of insurance a heads-up to us all to check our travel insurance particularly the height limit. Just checked ours and it covers trekking, hiking etc up to 6000 metres. We often go up to the top of Haleakala on Maui which is just over 10,000 feet(3000m) and Mauna Kea on Big Island which is over 13,000 feet (4000M). I don't have any issues at 10,000 feet but walking around the summit of Mauna Kea you do really notice the altitude and have to take it slowly.
One would have thought that IAG would have consistent clear policies across their companies that allowed flexibility for circumstances like this.