V,
A great dagger and I am glad to see you talked yourself out of it again! Smile.

My guess would be a modified Klaas 1st, its certainly unique and a pattern adopted and enhanced by Voos as shown here on another thread and with the same crossguard EMIL VOOS.

Maybe Voos dabbled in the early days with a design of their own but I remember reading a Wittmann description of the same crossguard and it was described as a modified Klaas variant.
A wonderful addition to your early collection of outstanding army daggers, I almost wish choosing this one over the Weyersburg!

Jon