Lightroom 4.3 will not sync images on macOS 11.2.3

System: Late 2019 15 inch Macbook Pro - Big Sur v11.2.3

Lightroom CC v4.3

*Disclaimer: please don't suggest the fixes previously mentioned in the "solved" thread pertaining to this issue, ie. "filter by sync status", "check deleted folder", "make a minor change such as flagging to unstick the sync". None of these will work. Even if they did, they don't address the root of the issue and shouldn't be considered proper fixes to this bug.

I'm having the same issue that many other users seem to have - my imported photos refuse to sync to the Creative Cloud, making them innaccesible to me on other platforms. Additionally, my sync status window now permanently says I have 50 photos syncing, but these photos are nowhere to be found.

Basic rundown of my past 24 hours:

- Add photos to Lightroom via card reader on my Macbook

- Photos are imported, wait for photos to sync

- After 5 hours photos never sync, give a star rating to all stuck photos

- Another hour, still stuck, flag all stuck photos

- Next day, still not synced, delete everything, clear out the "deleted" folder, and repeat the aforementioned steps

- Still not synced, delete everything, clear out the "deleted" folder, but this time transfer photos from my SD card to an external SSD prior to importing. Repeat the first set of steps again.

Still not synced!

This is really really really really bad for my workflow, and really increases the potential for keeping my clients waiting. I would greatly appreciate if someone from Adobe support could advocate for properly diagnosing this bug. I've always had problems with sync errors (wild delays in syncing between devices, occasional edits and entire files going missing) which are already inexcusable considering the price of this product, but this sweeping error has made Lightroom entirely unusable. 

Thanks!

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