Thanks! That's exactly the thread and pages I was looking for. I searched too but the same keywords hits on many similar but unrelated stuff.

I couldn't find an exclusion for the Japanese cards anywhere, but I was hoping if anyone had actual data points in case the night credits are handled by Marriott and they were in fact bound by the same restrictions. Don't want an uphill battle even if it is AMEX that failed at documenting things. I guess I'll just have to try it and figure out.