I wonder what Zattl does with the bits of the goose it does not serve. After serving both wings and both legs, they must have at least half of the bird left. Do they take these best bits home? Do they sell them on some black market?
Apart from being extremely small, it’s also a below-average goose, cooked and warmed up over a long period of time and generally handled with no love whatsoever. The meat is kept from getting dry by a huge amount of sauce and possibly (though I cannot guarantee that) by boiling it beforehand. The result is the meat that looks and tastes more like chicken that goose.
Add to this the sad fact that on the inside Zattl is an extremely busy, noisy, and uncozy place with overworked and inattentive waiters, and you can easily reach the decision of never having another goose there again.