Ok, thats good news. Check if the SBK from your photo matches the "secure_boot_key" in your prod.keys file.
If it is, first thing: Make a FULL backup of the current state of your Switch. BOOT0 AND BOOT1 AND SYSTEM.
It does not matter that they are not working right now, but you might need them if something goes wrong. (like it already did)
With this, it should be possible to >RECREATE< your NAND. You should now be able to find someone able to help you witht that.
Remember: Without a valid certificate, which incognito removed (and you should have a backup of on the SD used at that time), you will not be able to use Nintendo Services.