I wonder if something got corrupted when you were saving the file. I would try creating the HTML file again (as a new file and copy over the content of the file) and saving it as .html.
If you’d like someone to double check it for you, perhaps upload it to Dropbox or Droplr so that one of us can test it locally for you.
I was able to open up the file successfully. It didn’t auto-launch into my browser though (Chrome) but dragging documentation.html into the tab bar worked fine. I suspect the lack of auto-launch is most likely an issue with my setup.
You should be able to resubmit it and maybe just leave a short note to the reviewer that the documentation issue has been checked.