Glashutte Lohnberg, appear to have be around before and after WWII. The range of glass appears to include laboratory and domestic pieces.
There is an internet reference to a exiled Sudeten German engineer by the name of Zippe, whose re-located company supplied glass-making equipment to Glaswerk Wertheim.
Allegedly still a small family company, run by the Zippes, it might be worth asking them what they know. Certainly, little other info on-line.http://www.zippe.de