You'd have to ask Zeddicus but my bet would be they are Posing in Poser and transferring to DAZ rather than the other way around. There are converters that take a Poser Pose file and convert it to DAZ without a problem.

That script you are using is pretty old though. The last update was 2011. You aren't trying to pose a later Genesis figure then export that for V4.2 are you? I'm pretty sure it can't handle that at all. It was written before they existed.