Hmmmm. So the ball you are asking for, a ball that can push through the heads (presumably a bit worn) with backend recovery thru carry down usually the answer to that is either a pearl particle ball or a hybrid.  When I have exactly that condition I always go to my Prodigy (R2X pearl with ETM is essentially a pearl particle ball).  I am wondering what polish you have on your Prodigy - maybe that is getting in the ETM and rendering useless in carrydown?  Have you tried bringing your Prodigy back to original 4000 without the polish?

Prodigy aside maybe a Modern Marvel is another answer.  That ball is a bit smoother but that may do the job.  I would strongly recommend whatever solution you come up with to lay off the polish on a ball you are looking to navigate through backends with carrydown.

The Prodigy was a strong symmetrical ball. Keyword, symmetrical. However, by polishing the ball, you made it push longer than intended. I would suggest adding surface to that ball to make it hook earlier and be the rollier ball it was designed for, thereby, handling you carrydown issue. Then drilling some thing in line of a modern marvel or berserk if you wanted to stay symmetrical or critical theory for something asym with a big backend. Critical Theory is about as backendish as you going to get with a the storm/roto line, high diff, high intermediate diff.