Must... resist... soapbox...
Ok, I'll keep it to a minimum and on task. Traditionally, Germans do not categorize their beers as "ale". That's something specific to English/Belgian/French/Western brewing culture. Kölsh and Alt are considered Obergäriges Lagerbier, which means "top fermenting lager beer." Top fermenting, or sacch. cerevisiae (what we usually mean when we say ale yeast), is the yeast species that WLP029 is, and you're correct that it should be fermented at warmer temperatures. And as previously mentioned, go ahead and bring it as close to freezing after fermentation completes and hold it there for as long as you can stand it. I've gone for 8 weeks at about 30F and not had an issue with bottle conditioning. Be advised, though, that the krausen from WLP029 REALLY likes to hang around the top of the fermenter, and it might take much longer than usual for the yeast to drop.
You can thank the Reinheitsgebot from Köln for this particular quirk of history, as their version of the "purity" law prevented them from using bottom-fermenting yeast.
And go ahead and call your beer a lager if you want!