Firstly I very much doubt many Guide Dog owners would wish to take their dog on a long haul holiday.
As someone who has grown up surrounded by these amazing dogs, I know that they only work best when in their local environment. Taking a dog which has say worked all it's life in a UK town/village and then transport it to say LA would be a waste of time and effort.
Cars on the different side of the road, different pedestrian crossings, and the owner not having a clue where he/she is going, not to mention the unusual heat, the dog would be a shade of it's normal self and would much prefer to be on it's own holiday i.e. running around the local woods rolling in all sorts of mud/fox ****, and being looked after by some soft Guide Dog Groupie who gives out sasuages after each dow-eyed gaze!
But for those very very few owners who do decide to take their dog on a long haul trip, e.g. emigrating/long duration business trip, I know that they will probably be the best behaved thing in the cabin and will amaze cabin crew and passengers alike! People with Allergies can be relocated in the cabin, and toilet breaks can be managed in a discreet, suitable and hygenic manner I'm sure, with most blind people having a sighted helper with them on such a trip.