Big if
If the camera was at fault, most likely a broken flex cable, you would have to do a teardown and replace it. The problem with this assumption is that the n2DSXL does not have a 3D mode unlike the n3DSXL which will behave weird if its camera is bad, so the n2DSXL doesn't utilize the camera at idle??
I don't know if the n2DSXL has a pre-check for when communicating with its accessory parts when booting up. The 3DS family of systems are horrible in that they don't have safety redundancy when there's a hardware issue arises.
- ie, old 3DS and old 2DS crashes if WiFi module isn't seated correctly
- n3DSXL boots with black screens and music playing in HOME Menu in a seemingly semi-bricked state
- not sure what funky hardware issues the n2DSXL has and how they manifest as the model is relatively new, so not as common
***
I have one last thing to ask. Do you happen to have an NTRboot flashcart inserted in your n2DSXL?
There was one person in another thread who was struggling to boot his n3DSXL after unbricking and updating his custom firmware from A9LH to B9S.
He had a weird issue where his flashcart was preventing him from properly booting into HOME Menu until it was removed from the game slot. Something to do with the flashcart kept in NTRboot mode versus DS mode.