Old thread but im having the same problem currently, i was thinking though, isnt the usual cause for the pop up of “checking if software can be played” that you are not on your primary console, and if so you can not fix it on a banned console, because to make the console primary you need to go to the eshop and you cant do that, and also if you want to fake link an account you can’t (at least i can’t), when i tried it (linkhalo and tinfoil) i linked the account, rebooted and when i checked the software it hit me with 2124-0220, A nintendo account is required, so basically i have no way to go. i am no expert on CFW on switch so if i am wrong someone please point me out on it