flaked wheat IS unmalted.
However flaked is pre-gelatinizated so you don't have to worry about that aspect. whole unmalted wheat berries have a gelatinization temp around the mid to high 150s if I recall. but that is best case scenario with a grind close to flour.
so with the flaked wheat the starch will be readily available to the enzymes for conversion where the un-flaked wheat the starch has to gelatinize first. which is may or may not do completely.
I did know the flaked wheat was unmalted. I should have mentioned that so it wouldn't be confusing. I have heard of people "cooking" the wheat berries separately to gelatinize them, and then adding the berries to the mash. Of course, if I didn't get a total conversion, the mash would be a little cloudy--which isn't a bad thing for a witbier.