I entered in the local NHC San Diego qualifier and took Silver, but its different than the OPs version. For instance the WLP570 alone is a fantastic beer. 570 is from the Moortgat brewery (Duvel) and its going to give you a very similar flavor profile to DT. The problem with culturing yeast from a bottle out is that Belgian breweries often employ a second or even third yeast strain for bottle conditioning than those used in primary or secondary fermentation. You may not end up with anything close to the pure primary yeast strain. I feel the best option is to use a pure strain such as the one from White labs. I would hazard a guess that these yeasts from Hughye, Westmalle, Moortgat, Van Steenberge etc. all originated from a common ancestor.
Also, having been to Hughye last month, and several other breweries, a common thread was:
1) 75 minute boil to minimize color reactions, DMS was gone by then
2) no candi syrup or rocks in light colored beers....table sugar only
3) minimal specialty grains, mostly Pilsener
4) no spices, all yeast derived
There was a high temp finish on the golden ales and a significant lagering period but often the lagering was off the yeast cake with a fresh dose of yeast and a 'small' amount of additional sugar (pre bottle).