In my experience from April:

You will find the best rates if you book at Outrigger, especially if you select Discovery Member rates in the search options.

You will have to email the hotel to add your Discovery member number to the booking. As long as you do that, you will receive (or at least be eligible for) member benefits, D$ and elite nights.

There are some rates that explicitly exclude Discovery member benefits and elite status night credit, so avoid those.

I did not like the hotel at all. The club lounge in particular was very poor. You have to cross a very busy and dangerous road to get to the restaurants and beach. I was so unimpressed that I cancelled my stay and left about an hour after I had checked in.