I agree. I wrote a single thread and a thread-pool Python script outside of galaxy to test. I posted those results in drmaa library threads and munge: Invalid Credential Format . Single-thread submission works.
My skill-set falls short on digging into the code and creating a wrapper to lock the submission on Galaxy. I thought about spinning up PULSAR and using that to submit the job to the SGE Cluster as a means to bypass the drmaa job runner. Could that act as a work-around?