I wonder, if it is any interest to you:

My mother-in-law's father was Izsak-Yitchok Yaakov Friedmann    --a Kohen- son of   Dayan, Harav Zvi HaKohen Friedmann from Beregszasz? Kezmarok? 

Izsak,-- Yitchok Yaakov Friedmann was a 'Sochet' in OZD-Hungary--before the War--His wife was Sarah Felberbaum--I am not aware--it might be that Sarah had a secular name as well.

OZD is near Miskolc.

I am not aware that they lived in Wien  or not, or if they had a restaurant or not.

On a different note: I also like to mention that  to my knowledge, there was  a Nadudvar  ?  or Nadudvari ? in Hungary as well.

Best wishes to you all and wishing you success in your research.

Veronika Pachtinger