Mystery solved, thanks to a terribly kind person on the Swedish glass board with connections to Åke Bergqvist, ex-Strömbergshyttan engraver.
Hovmantorp's New Glassworks closed in 1977 and Kronoberg Glas, in 1979, bought Hovmantorp's design catalogue, including the Rune Strand designs, and all remaining cullet from the factory owners - hence the exactitude to Hovmantorp's green blocks. Von Wendel worked for Kronoberg Glas from 1981, engraving these glass blocks.
I no longer have to talk to myself in this thread.