Uhhhh, okay, wow. You do realize that you're not supposed to factory reset the Switch while you have ANYTHING customized system-wise on it, right? This includes anything that modifies system titles or packages (such as the home menu or chat blacklist), including themes among other things. You'll need to remake a new emunand (I assume that's where your error is, since you said sysnand works) and lose all your data, as it is likely that something is completely borked in your emunand. The Nintendo support site says that the most likely fix is to completely power cycle the Switch, which means having your jig handy and disabling AutoRCM. If that doesn't work, then your only option is indeed to make a new emunand.