I do not understand the difference between ambient display and always on display? It's the same thing I thought. The display is active and so DT2W works.It works in the AOD on crDroid...so yes it does support DT2W
But not if the display is off.
In LOS15 for A5 - as far as I understood - was an option for DT2W without ambient display, which drew plenty of power. Probably because the display was active but black.
Just my 2cents