Just a brief posting, as I'm up to my eyeballs in three other projects...
In Mogens Schluter's brief history of Kastrup-Holmegaard he only briefly mentions the 1925 exhibition, and it seems that the only entry by Holmegaard was an incredibly beautiful stemware range called 'Tranquebar', designed by Orla Juul Neilsen. He doesn't go into what caused Danish glass, after 100 years, to suddenly move into modern art glass, unfortunately.
Tranquebar, 1925Looking at the glass production of other Scandinavian companies around this time, and later, it appears that Denmark was a bit of a slow-burner until at least the mid-late 1930s, even though JE Bang's designs had been gathering awards since the late 1920s (most notably at the 1929 Barcelona World Fair).