Using samba you likely did create some files/directories with capital letters. Do:
mkdir -p /storage/.config/firmware/rtw88
wget -P /storage/.config/firmware/rtw88 https://git.kernel.org/pub/scm/linux/kernel/git/firmware/linux-firmware.git/plain/rtw88/rtw8822c_fw.bin
You may have to download rtw8822c_wow_fw.bin too.
I think you have inadvertently got me to download the wrong version with that. A prior post said
PuTTY is refusing to allow me to paste in Mint. It worked once now refuses. I have downloaded both firmwares but the WOW version is also 22c not 21c. I think it should only be the 21c version if I am not mistaken.
All done correctly using PuTTY and the correct firmware, I think, which is version 21c but still not working. Link below.
http://ix.io/30DG
Found a link which seems to match problem.
LKML: Kai-Heng Feng: [PATCH] rtw88: 8821c: Add RFE 2 support
The WiFi works okay in Linux Mint but wasn't installed initially. I had to install third party drivers which were in the drivers section of that.