By way of an update, I was finally able to submit my missing stay request form yesterday after waiting the 10 days. Got an email this morning saying they will respond in 5 - 7 business days.

This is insane. So, in total, it could be almost 3 weeks after checkout that my stay is credited. In that time, I will have stayed 4 different hotels where I won't have received my plat benefits that I should have if the system worked like it should. I just don't get why it takes so long. I had another stay last Friday, credited the next day.