To me, all three Koummyas look rather low end touristy 20th century.
More about Koummyas you can find at the link below:
http://vikingsword.com/ethsword/koummya/index.html
The Jambiya does not appear to be ethnographically specific/traditional and it is definitely not Omani or Yemeni, in my opinion. The workmanship doesn't appear to be neither Indian or Pakistani but more like African.