According to the March 2014 blog post, OpenShift now got rid of some directories like wsgi/, wsgi/static/, data/ and libs/.
Given I used wsgi/static for this purpose
According to openshift.conf.erb, it seems like it checks if you have a $OPENSHIFT_REPO_DIR/wsgi/static directory and it keeps it working. I haven't verified that this works, but it looks like it should.
$OPENSHIFT_REPO_DIR/wsgi/static