I have been exposed to dogs of all ages in my working career and in my sport (agility) for 15 or so years. I have seen many Dachsunds and Papilion's - very few had health issues. My mum & auntie both had a mini long hair daccy's all thru my childhood - both lived to a ripe old age. Only prob mum's had was a broke it leg when it fell from the parcel shelf of the car in a car accident.
As for hip probs and luxating patella's, I have seen very few in smaller breeds in proportion to numbers of dogs I have seen. Mostly the probs I have seen have been bad teeth, overweight, under/overshot jaws or umbilical hernia .
If you have seen someone with this cross perhaps you could talk to them? How old was the dog? Who bred it? Blah blah blah.
What ever you do you are taking a risk, weather it be pure bred or a cross... at the end of the day, If you want to own a dog, insure it and make sure you are willing to spend money on it. Everyone will offer you advice - take what you need from those that do - put value in the advice from those that are quailifed... Vets for health & Nutrition, Trainers for training, groomers for grooming.
Owning a dog is a luxury and carries many benefits and it is very true, the more you put in (time & care) the more you get out.
IMO :lol: