Take a little care Poppy....that site is the one I did my little quiz about the goose from!!
It may all be totally correct, but I only know two things....I had a lot of Princess House Crystal at one time, and I am sure I saw one of these birds with a label when I was looking for pieces.
As far as the French Vannes Crystal is concerned, I know they do bowl shaped animals as pipe holders, but I can't vouch for the fact they may or may not have made for Princess House Crystal. I always thought Princess House Crystal was made in Germany (Bleikristall???) but they may have had their glass pieces made in other places.
Still worth your investigating....don't take the first thing you see as Gospel.....even though it might turn out to be correct!!!!