Ideally, your CC should be 0. Since your overnight FC loss is greater than 1 ppm you are still killing live algae. Keep up with the FC at 20 ppm which is shock level for your amount of CYA. I had a very green pool one time after a long absence. It took 6 days of shocking before the water was a cloudy blue and then 10 days to get it filtered clean. I didn't vacuum. I just swished the brush over the pool bottom a few times each day to stir things up and let the skimmer sock catch the fallout. I did change skimmer socks a lot during that time.

About the Poly-60, my understanding is that the high chlorine levels will eat it up (break it down) so I wouldn't add any, but I could be wrong on that. Try the skimmer socks if you haven't already. They do catch a whole lot of fine debris.