Would a grapple/hook on the end of a rope work? Let it carry down to the clog from above and hopefully "catch" some debris that can then be pulled up and loosened. Alternatively, can you get to it from below? Or attach a hook/claw on your pole and work it from above?

A word of caution, don't underestimate the strength of the "suck" if the clog suddenly breaks free. Make sure you are in no danger of being sucked into the pipe. I have a neighbor that had a kids basketball get in his drain pipe once and he was battling it from above and finally cleared the obstruction and was amazed at the hydraulic power as that clog was freed.