Unfortunately we need the keys. While KeyY (in
movable.sed) might be obtainable via the bruteforce service if the friend code of this console has been shared (saved on a friend's console), the same cannot be said for the rest (I guess the OTP is needed here).
KeyY is enough for decrypting the data on the SD. All things on NAND can't be accessed this way (Streetpass, Mii stuff, Face Raiders, friend list and whatever data all the preinstalled titles have).
Reading out the NAND via hardmod is possible if the NAND isn't damaged. But without embedded essentials.exefs the encrypted data is just random garbage.
I have no further ideas than what I told you in the
previous thread. The thing must turn on to retrieve OTP -- and if the board is absolutely toast beyond any repair, the only small hope is the risky and complicated procedure of transplanting the "brain" (CPU and NAND) to a donor board. I do not even know for sure it is possible on 3DS this way. I know it works on Wii (seen a proof of concept) and heard about the same method for data recovery on iPhone when the board cannot even be revived for a short amount of time.
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Getting access to purchased software pretty easy if you had an NNID linked: Call Nintendo, say them the console is completely broken and ask them to unlink the NNID server side. You can then link it to another 2DS or 3DS and download your games from eShop. If they ask to send in the device for repair, I would answer something like: "Oh. I already gave it to the recycling center not knowing I can't simply link my NNID to a new one."
