I'd like to read that comment, but then again there's also a lot of BS being posted underneath Youtube videos.

Jon stated the song was about his time at the Powerstation Studios where he worked through the nights to be able to get some demos done and recorded. I highly doubt that this song was written at that time as well.
When it comes to demo recordings there actually isn't anything around besides "We Rule The Night" which made it's way onto the box set. I remember a comment by one of the band members that they were so afraid of someone stealing their tapes that they "literally had to carry 'em with us from and to the studio". I'm pretty sure this was around the Fahrenheit era. This might be the reason why others didn't really get their hands on any of the demo batches since I guess that the leaked one's from the other albums of that decade where usually passed around by some third-party people. Furthermore, given the very short amount of time they had for that album ("you have your whole life to write the first one and then six weeks for the second one"), I don't think there was much of a demoing process anyway. A statement which Jon made in an MTV interview in '89 suits this thought of mine:
"...people have heard of us, quick, let's get another album in their face straight away. And instead of taking our time and thinking it out and letting the songs breathe we really, really rushed!"
There are two song titles that we know of which were "Afraid of the Night" (I presume this was the pre-Hardest Part Is The Night track or its working title) and "Danger Zone". Jon talked about these two in an interview he gave to MTV in early '85, but a recording of those has yet to surface.