That's probably one of the recent firmware update changes, similar to the Switch 2. I had to update my Switch 2 in order to activate the microSD card slot.
In order to send hekate payload, you don't need to have SD card inserted for the first time as stated here: https://switch.hacks.guide/user_guide/rcm/sending_payload
However, your SD card probably won't work in OFW, though. Can't really test that out on my end without updating my OFW to the lastest firmware. Still, you should be able to use emuNAND.
I see. Later in the guide it tells you to copy the Nintendo folder which I don't have, so in preperarion I wanted to create that using the Switch. The SD card had be used for the Steam Deck, so there's no Nintendo folder to begin with, nor does it even recognize the SD to begin with on the Windows based PC. The PC detects the SD card in Disk Management though, so it's not corrupted. The SD is barely used as most of my files are in the Steam Deck drive lol







