I have a SanDisk Ultra 400GB formated to exFAT, and I only have one NSP file, and no games on it, just to make sure I had space.
I tried downloading the latest build "tinfoil-32cdc0b" from the link you provided, and when I load that through Homebrew, it crashes as soon as I try to open it.
Error code: 2234-0095
An error has occurred.
I have tried formating my Micro SD Card through my Mac and Switch, and I have installed Tinfoil through my SD card reader on Mac, and on Windows through FTP (FileZilla).
I also used the method to get exFAT support on my Switch without updating, with the first SD Card I had, not sure if I need to do it again, when I changed SD Card, I guess not since, my Switch can read my new SD Card.
Thanks for helping me