Main beam is bi-xenon, so uses the D3S.
The other main beam bulb, which should only be used to flash when the headlights are off is an H8, I think.
So is mine. It is also for a quick flash, yes.
I know that you said that your car works differently though, but the bulbs should be the same.
I wonder if someone has modified the wiring on your car for some reason?
My lamps work fine, to my knowledge, but when you look at the bulb from the front of the lamp, the main beam bulb looks different to the D3S bulb. It look's more like a bulb from a normal H group base.
If you decide to remove the bumper so that you can remove the headlights for better access, be very careful not to move the adjusters that align the headlamp housing as they are a pain to re-adjust.