UPDATE: I contacted MSI who, to my surprise, were rather quick to respond and with decent (though my problem still persists) instructions.
The first reply I received from them instructed me to download the B130 Update tool at their google drive link, and click the update buttons in the following order: M481->SPI->NUC126. I would share this link, but as others have noted, this is technically a confidential response from them and I do not wish to find myself in the middle of a legal debackle.
So I extracted the .zip folder to my desktop, went through my entire directory by hand and deleted anything associated with MSI (literally anything), ran the windows uninstaller on the MSI Center app, ran the official MSI Uninstaller to be sure, and then booted into safe mode. (Lets out the side of an exhausted 80 year old man)
Once in safe mode I then opened the folder I had extracted to my desktop and ran the B130 update tool as an administrator, clicking the buttons in the prescribed order. I encountered the same problem, M481 never finishes updating; it just keeps cycling.
I then emailed MSI with my results, and they gave me a second set of instructions. They advised me (in as few words and in this order) to unplug my 24 pin power cable, remove the motherboard battery for more than 5 minutes, and then reinstall it. Then enter windows and try to reflash the firmware.
Here are the steps that I took in chronological order:
1) leave MSI Center installed on my computer
2) shut down computer
3) turn off main power switch for computer PSU
4) disconnect wall plug for PSU
5) Disconnect the 24pin power supply cable from the motherboard.
6) disconnect the 12 pin power cable from the GPU
7) remove gpu to access motherboard battery
8) remove motherboard battery and wait for 5-10 minutes.
9) Once enough time had elapsed I reassembled the computer
10) once logged back into windows, I ran the firmware flashing software MSI sent me as an administrator
11) I clicked on M481 first but just like before it never finishes updating.
12) I repeat everything a second time in case I didn't leave the motherboard battery out long enough.
I'm almost willing to disassemble my K360 just to try and find some hidden hard reset button. I appreciate any help that anyone can provide on this issue.