not that I'd have known from experience, but according to Mark Hill's booklet apparently Josef Pravec - probably earlier than Jelinek - also designed pieces using cut lenses, which were made by Podebrady glassworks.
I probably shouldn't say this one is unlikely to be Borsk Sklo, since Czech material isn't my area remotely - though some of their work is decorated with cut lenses - oval and round.
Perhaps Anik might be able to help with this one.

Agree, nice piece.