I tried the magnet trick before, its pressing buttons and keeping the magnet still, I have a very twitchy body since chemotherapy and spaz fits, also bad memory because I used to be able to mod 3ds consoles like water off a ducks back, downgrading, setting up for Gateway or installing CFWs..... Now its all blank.There are instructions on that page for how to test a suitable magnet. You don't even need to hold in in place very long. You can probably find something suitable at your local dollar store (if you have those).
Are you sure "Mii Plaza extdata" means what you think it means? Some Mii Plaza data is stored on the SD card, but I'm not sure how useful it is without data from the NAND.
Those files are encrypted and you will need to decrypt them before you can do anything with them. See https://gbatemp.net/threads/restore-save-data-from-dead-3ds-2ds.606907/ . (Be sure to read the first couple of posts in the thread.)
I'm scared to even touch the 2 working consoles one boots for Gateway and the other was the same but when I was starting to forget, I had forgotten what I had done, so I changed it to CFW and now I've forgotten everything even the initial trigger that boots.
But ill try find a strong coin size magnet off amazon or something.










