@peterctucker Thank you so much, you saved me! 
Just going to type out the solution should someone come across this post in the future.
If you accidentally check...
...the fix is to download this script:
https://github.com/VladDBA/Asus-Router-Config-Decoder
Pastebin script backup:
https://pastebin.com/5rn7FMt3
Open up powershell as admin, and run the script:
It will give you an output of something like:
Log back into your router with the username and password that consists of EIGHT X's: xxxxxxxx
From there, change your username & password in:
Then change your Wifi passwords, and DDNS.
Finally, once everything is setup make a GOOD backup of your config file.
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