as I agree with what the others have said (I wouldnt want to do this trip myself, too long distances per day and I've done a fair amount of touring) I would like to add that of the time I have spend looking around on Bike Forums, the touring section is quite unique for respectful, thought out and insightful comments.

My wife likes biking, but not to the extent as I, so last summer we did an organized 6 day tour, still camping, but the event organizers truck your stuff to the days end point and they provide meals. (look up "Velo Quebec-Le Grand Tour" if you want to see what sort of thing it is, about 1800 participants)

Yes this was pricier than doing something on our own, but having support people on bikes, support vans to pick you up if too tired to finish the day or get injured, THIS is what appealed to my wife. It was fun for her, she took advantage of the "return home to base" trucks a few times, but she still did 60, 70, even over 100kms per day (40, 45, over 60 miles). I carried the days stuff with us (I always have flat repair kit, pump, extra food etc) so she would have no weight, especially as we had lots of climbing for the first 3-4 days)

but it was fun for her and not overly ambitious.

to give you an idea of average speeds, when I toured I used to average about 17kph or just over 10 miles per hour. Unloaded, on a day to enjoy myself, I do about that still, maybe 20kph max. Yes, hills, wind, getting tired all plays a part, but honestly, as someone who rides a fair amount and who knows how it is to be on a bike all day (unlike your wife) 10mph average is a realistic average. A LHT is not a light road bike, and weight notwithstanding, spending 4 or 5 hours actually riding is hard, for your hands, your neck, your bum. Your wife doesnt bike, so this is all going to be new to her (the pains I mean) she wont know what to expect nor what to adjust to help matters. Her keester or other parts might hurt like hell and think that "that is normal" and put up with it to her detriment. She could also be ok for the comfort side of things but she still will be sore everywhere even after an easy hour long ride.

I mentioned the organized trip thing as a possible alternative, dont know if that sort of thing exists down there. But even if it doesnt, even just little hour long rides along some pretty areas this season could perhaps whet her appetite for biking.

cheers