Just a quick data point for you guys:

I have successfully completed the platinum challenge!

1) My account showed platinum nearly instantly and is supposed to be good into 2020.
2) I signed up for this in September before they changed the terms to disallow award nights.
3) As a result, my awards nights did count. I did a mix of paid and award nights.
4) I had to call to get someone to add the awards night and make sure they counted. I would recommend asking for a supervisor for this step as most (all?) front line phone reps have no clue about this.