Even though your thread is very old I have found some information which might be interesting to you http://www.tachna.com/Tachna_family%20tree_outline.pdf
I was researching my cousin's family - his great grandfather was Philip Cohen and his parents were Benjamin and Byla Cohen of Plock, Poland. I found the above link and page and noticed that Szajka (Shia) Cohen died in Argentina so thought they might be related to you?
All the names you mention are in the document but they might not be the people you are looking.
Let me know?