sorry, not a clue I'm afraid - looks attractive. I think you'll find that most folk here would call your 'gilt/gold knot, a knop. fwiw I'd suggest the upper case W may possibly have been the initial of the original owner of this piece, rather than a maker, which is what you might have been thinking. I agree, this may be a champers flute, but I suppose always an outside chance it's a stem vase of sorts. It won't help remotely with an id, but out of interest you might care to let us know the height please. Gilt/gold flecking, or similar, has been used by some of the Gulf of Venice house in recent years - not suggesting it is but gold applied like this is know from the generic Murano makers - is the gold on the inside of the glass, or the outside?
Again, just out of interest, is the W etched (acid application), or might it be scratched on?