Wow! Well, you're certainly in the realm of "expert" at this point. I've never tried a classic Coke flush. Sounds tasty. *grin*
Unfortunately, I don't have any good ideas for you. If anything comes to mind, I'll come back to post, but it seems like you just have a lot of flushing you need to complete. I have never experienced what you describe (nor have I had such phenomenal results from a flush, but perhaps I'll try one of the two you mention to see what happens!).