I can help here.
Enter the console of the docker then:
cd usr/bin/nzbget_bin
nano cacert.pem
After you're in the editor, make sure you're at the top of the file. Should look like this:
|##
## Bundle of CA Root Certificates
##
Press Alt + A to start highlighting a block. Pgdn until the entire file is highlighted then Ctrl + K to delete the contents.
Copy + paste new contents from the fixed .pem in your link.
Control + X to exit. Y to confirm write changes. Enter to confirm file name.
Restart the nzbget docker.
Finished.
