Richard Gott, "an embryonic Communist Party formed in 1925 by socialists attracted to the Russian revolution, several of the more prominent Cuban communists were Jews from Eastern Europe, some of whom found it easier to speak Yiddish rather than Spanish. One of them Yunger Semjovich, was to survive into the early years of the Revolution in 1959 under the name of
Fabio Grobart. Distrust of the communists as "foreign thence Jewish and beholden to Moscow," as prevalent on the nationalist left as on the right was one of the obstacles facing the party."
Archive.org.
There doesn't seem to be anything here yet