If you want to get this figured out, I'd recommend the Nintendo Hacking discord linked to from the guide.
Alternatively, because you're still on SysNAND 9.2.0, I'm pretty sure you could just run through the guide from the start (Since you can just use soundhax to install b9s). Unfortunately...
Did you follow:
9. Delete any existing .bin payloads in the /luma/payloads/ folder on your SD card as they will not be compatible with boot9strap compatible Luma3DS versions
Before putting the other payloads in that folder? Specifically the SafeB9SInstaller bin.
new smilie ^
its much better than the rest (except for the fact that only touhou fans really understand it and im not a touhou fan and yes its bad apple thats like the testing thingy
)