I tried it in ubuntu (on windows) and got the same result. Cygwin bundled with goaccess didn't have the locale command built-in. I also tried setting the LANG variable but didn't make a difference. Also tried converting the file from Windows (DOS) to unix, no difference, same error.
The space was the issue, I still don't get where that is coming from and why it persists (on the new first line) when I delete the line but I just read the files in backward with tac and was able to get my data imported.