It's impossible to forecast, because it depends on how that particular hotel (in fact how a particular person at that particular hotel) "merges" your two reservations or "extends" your reservation. The only thing I can say for certain is that it may or may not count, independently in each case (ie, both cases might count, or both cases might not count, or one case might count and the other might not count).

So since it's impossible to predict, you just have to wait (unless you're willing to cancel the second night and move the second night to a different hotel). Fortunately, it's still only September, and the promo lasts until December, so you'll have some time to do "make-up" stays if you find out for "certain" that one or the other or both didn't count toward your app task.

But what I don't know is how long app tasks take to post compared to simple stay posts. They may post at the same or they may post significantly later, I don't know. I've never had an app task (except several years ago back when it didn't really require an app), so I have no experience with this.