Could Kmetz be Kumec or Kumetz?
My great-great-grandfather was Usher Kumec from Konskie (Poland) descendant of other Kumetz rabbis from same place. He was a rabbi in Belchatow, married to Frajdla Brandes and they had my greatgrandmother Ryfka (b. 1839) and others, I suppose. See my note in Kummetz board.
Any relation?
Lala