Id like to weigh in to the conversation, as I'm a Kadelka too. I'm researching my family too.
As far as I know, the "Kadelka" name is from Poland. I've found a few Kadelka named people in Germany.
What I've been told about my family is that they immigrated to Hungary between WWI and WWII.
Back in Poland from what I've been told the Kadelka family was a family of regional Governors.
If you find out more about the family, do let me know please, I'm very interested...