OcBinaryData VS ProperTree

HfsPlus.efi is missing, get that from this link and then put it in your Drivers folder: https://github.com/acidanthera/OcBinaryData/blob/master/Drivers/HfsPlus.efi

Fixed loading macOS with legacy boot without Apple Secure Boot: there is a new PE (Portable Executable) loader that broke legacy boot, blocking the loading of legacy drivers as HfsPlusLegacy and preventing OpenCore from booting on legacy systems when Apple Secure Boot is disabled. With this fix, legacy boot can work with or without Apple Secure Boot. This issue was detected after version 0.8.8 was released. While you are on 0.8.8, you must download the new versions of the drivers HfsPlusLegacy and ExFatDxeLegacy (the one/s that are necessary), available in Acidanthera. This is not required if you are on OpenCore 0.8.9.

Update Resources as well: https://github.com/acidanthera/OcBinaryData

Check if you have the latest resources Folder (included in OC Binary Data)

Copied from the latest OcBinaryData

I'm able to download and open up the zip as instructed, but as far as dropping the "ExFatDxeLegacy.efi" file into the right location on my ESP (which I understand to be my boot drive, where OCLP was originally installed), I'm at a total loss.

Have you tried downloading the version from https://github.com/acidanthera/OcBinaryData ?

Open the config in ProperTree (https://github.com/corpnewt/ProperTree) and do a clean snapshot (CMD-SHIFT-R). This will put all of the kexts in the right order.

Open your config.plist using ProperTree.

NO. Prebuilts are a bad way to start. They are not updated and aren't configured to your specific needs. Make your own EFI and also don't use OCAT, use ProperTree which can do OC specific things like OC (clean) snapshots.

ProperTree

Try looking into a program called ProperTree. Has a GUI implementation to easily edit https://github.com/corpnewt/ProperTree

Used the Ryzen and Threadripper(17h and 19h) OpenCore Install Guide for with OpenCore v0.8.7 in combination with OpenCore Auxillary Tools, Sanity Checker & ProperTree.

Use propertree. It is hands down, the best IMO. https://github.com/corpnewt/ProperTree

You need to mount your EFI partition (find a tool online or use command line). In it you should find "EFI/OC/config.plist". Open the file with Propertree or another plist editor and make the changes.

If anything, keep .contentFlavour files removed and try updating your config.plist using ProperTree or some other plist editor which just makes it easier to read. Sorry I couldn't be of much help but its the best I've got right now haha.