Hi Dirk, To answer your question above, The piece you found is, IMHO very much in the style of Palda, as much as yours is.
I did some quick research on Glasfachschule Steinschönau. I also looked for examples of other work from Haida where Palda was located and could not really find anything else quite as strong in design as Palda's work... not to say it is not out there of course.... The examples I found were all in the vein of being much "busier" in terms of details and not having the bold and defined statements these decorations make. Or, they went the other way and were quite simple in terms of design.....
Based on what I have seen, I would lean much more in the direction of Palda than Glasfachschule Steinschönau, or any other examples of work from houses in the Nový Bor region that I have seen.
I collect some Deco, and from previous research it is my understanding that there is limited knowledge about the history and development of Palda, and that one of the greatest sources of information for the company's designs comes form their 1938 - 50 year anniversary catalog. That is the source of the images in Truitt I.
I try to be reasonably thorough in my research, but this is, of course, just my humble opinion....
Craig