Coming back with my data point on this...
I got the night credit and points! Including the double promo! I went and got my gold card first at the MLife desk before checking in and at that desk they noticed my hotel reservation didn't have my MLife number attached to it so they did it right at that desk. Then someone escorted me to the Stay Well lounge which is where Gold and above members get to skip the check in line. I was supposedly "upgraded" to a better view room but I wouldn't have noticed if they hadn't said anything. During check in, I asked if my Hyatt account was attached and they verified it was so my hopes were high. At check out I again verified that my Hyatt and MLife accounts were attached.
About 10 days later now, I noticed a big jump in nights and points and here she is in all it's glory!