Hi All, thanks so much for the help and advice. As of this morning the pool is clear and safe. It took two whole weeks!
I did eventually decide I had to color outside the TFP lines; the cloudiness just did not budge at all over 4 days +/-, during which I went through about 12 gallons of chlorine. While I'm putting most of the blame on my borderline-undersized filter and flow issues, I had a phosphate test done that showed over 1000ppb (probably not surprising being uncaged and on a golf course in SWFL). I'd already decided that an equipment upgrade was in order - which I want to have done ASAP - and there was no way I was going to have anything done with pumps and filters without the water being in top shape, so I decided to go with a remover knowing that it would serve to both lower the phosphate and give me flocculant action at the same time.
I kept the shirt in the skimmer the entire time, cleaning every few hours, and continued washing and trading between my two cartridges as often as I could. After the first night with the phosphate remover I could finally see the top of the third step, so I started running my robot with the fine silt basket installed and only for about 15 mins at a time. I couldn't go any longer because the basket was clogging almost immediately. Slowly but surely, however, I could run the robot longer and longer. It took a couple of days, but I was eventually able to see the drains and the robot was able to complete a full cycle. Over the last two days I was able to switch back to the standard basket, run the chlorine loss test and balance out the rest of the chemistry.
Everything now is clean and clear and my filter is actually happy! I still can't run the water feature and jets at full power at the same time, but my pressure is holding steady and low. I've been getting quotes on upgrades and will be deciding on install or DIY soon. I'll probably go larger than I need, but given this ordeal, I think I'll feel it money well spent.
Thanks again! I learned a ton and feel like I can keep this pool well maintained going forward. I'll have more questions soon, I'm sure.