I think you would be best to phone the airline and ask them about their 'exclusion' policy, then contact your insurance people and try to get to speak to someone sensible there to clarify the policy. (I know this will not be easy, but try to be persistent and keep on asking for a supervisor/more senior person until you get someone sensible). Make a note of their answers, as well as the name of the personyou spoke to and the date and time of your call.
Hope the spots are not chicken pox...