I have been trying to clone this beer for a long time now... Every time I tried I would get closer and closer, until one of my brew buddies suggested capturing and culturing the bottle yeast - the only variant I had not messed with up to this point.
I tried sometime last year around this date, but found the bottle dregs to be unresponsive. I waited until the summer because I thought there might be "fresher" bottles available, as there is more product turnover in the hot weather.
I took the dregs of two bottles of Schneider Weisse and stepped it up in a small flask... It took quite a bit of rousing and sterile air to get it going. After it fermented out, I washed it and stored it under sterile water in my yeast fridge... I recently got it going again to see how it would perform.
I had no issues getting it going a second time... 250ml of wort started OK with 30 minutes of sterile air to help it along... stepped up to 500ml, then into about 1.5 gallons of all grain light ale wort I had left over from a recent brew session - it really started to come alive in that all grain wort.
I let the fermentation get a full head of steam and ran out to buy a Muntons wheat beer kit to throw more wort at it... I made up 3.5 gallons of wort and dumped the 1.5 gallons of already fermenting wort on top of it... It took off real quick showing signs of real top cropping ability... I skimmed the brown trub off the top a few times to make sure that stuff did not fall to the bottom after fermentation subsided. This yeast is quite strong and gives a nice bread like smell when fermenting.
After 5 days I racked it off and was surprised by the taste... For a mixed/kit with the wrong hops it tastes pretty similar to a degassed original sample of that beer - The flavor profile is similar to the original but different from other liquid wheat beer yeasts I have tried in the past (and was never quite right)
I let the beer sit on secondary for 1 week then bottled with a mixture of corn sugar and lager yeast... Can't wait to do a side by side taste comparison.
Now I have a nice strong sample under sterile water.
Hopefully the results will be good enough to try a full scale all grain batch soon.
So if your having trouble getting this yeast going from bottle samples, I would suggest waiting till the summer time to do it - seems to have worked for me.