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Update: Finally got it working. Here are the steps I followed for anyone running into issues.

0. Turn on usb debugging and oem unlocking on your phone if not already turned on. Plug your phone in at least once and allow click allow to your PC using adb with your phone.

1. Install the LATEST Google Drivers found here: https://dl.google.com/android/repository/usb_driver_r13-windows.zip. DO NOT download from other links from unverified sources. No need to install unsigned drivers.

2. Install ONLY the Qualcomm driver found in xxlMVPlxx 's mega link via the QDLoader HS-USB Driver_$ARCH_Setup.exe where $ARCH is your architecture, probably 64 bit. You'll need to extract the QDLoader HS-USB Driver.rar archive to get the proper binary.

3. Restart your PC, the Qualcomm driver should have prompted for a restart anyway

4. Before starting the process, Make sure the phone shows up as:

"Ports (COM & LPT) > Qualcomm HS-USB QDLoader 9008 (COM3)" (Note, the 9008 and COM3 might have different numbers, that is fine) while in EDL Mode in Device Manager.

Spoiler content hidden.

"Android Phone > Android ADB Interface" while in fastboot in device manager.

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5. Download, extract, and run the MSMDownload tool provided by Superboy58 here. The program will take a some time to open, don't be impatient here. Once open, click the start button

6. While the MSM Tool is running, poweroff your phone. Next, press andhold down the volume up and volume down buttons at the same time while plugging in a data transfer ready usb cable between your pc and the phone. Continue holding down the volume rockers until the EDL tool states that it's downloading super.img. This should only take 10 to 20 seconds.

7. Once the tool is complete and the time stops counting up, you're safe to close out of the MSM tool. The phone should show a scary message about device corruption (see xxlMVPlxx 's photo in the original post). This is normal.

8. Download and extract the Android 10 global image by mauronofrio here. Make sure to extract it to a subfolder for cleanliness.

9. Open up the directory where the extracted image lives and run "fastboot flashing unlock_critical". The device will show you a prompt to unlock the bootloader, and you'll click unlock the bootloader. See xxlMVPlxx's image in the original post.

10. Download and extract my version of the flash-all.bat script (attached to this message) to the same directory you extracted the Android 10 global image to. My version of the script simply removes the wipe all data prompt and adds a fastboot --version and fastboot devices -l to the start of the script to ensure the device and binaries are properly working before flashing starts. Once I get a little better at batch scripting, I'll update the script to make sure each command runs properly and actually catches and reports errors.

11. Run flash-all.bat. NOTE: This is version of the script *will* wipe the device every time without prompt unlike the original script. Do not run it outside of this process. This should run to completion without errors and reboot the device.

11 a. If the device reboots with the T-Mobile boot animation rather than the international boot animation, unplug the device from the computer, power it off as soon as possible, power it back on to fastboot mode by holding volume up, volume down, and power at the same time, and plug it back into the PC. It should come up as "Android ADB Interface" in device manager again. Once you've verified it starts up correctly, re-run the flash-all.bat script. If the script reports ??????????? as your device's serial, close the script, hit volume down on the phone, and hit power to reboot the bootloader. If the script reports ?????????? or begins erroring again, power off the phone completely, unplug it, reboot into fastboot, plug it in, and try again.

12. If all went well, your device will reboot using the global boot boot animation (two white dots rotating around a big red dot). At this point you can install any rom of your choosing or simply use the device as normal and update to Android 11.

Hopes this helps some of you running into issues.