I didn't know the 1000th win thing existed

I got my 1000th win a long time ago but I didn't know about the special play with a riot employee thing when I got it. Would it still be possible for me to get in on that? I am available 5-9 pm central Monday through Thursday, 5pm-midnight Friday, and 12-9pm on the weekends. Also, would it be possible for me to bring a couple of my friends that also have 1000 wins if they have never done this either?

Also, I'm pretty far past 1k wins.. I'm sitting around 1350. Does this cause me to not be able to play with someone from riot?