TylerE, the buttons in the panel don’t show you the popover shortcut because they’re not the same thing. All of the popover shortcuts are, however, listed in the Write menu.
FlowerPower, the reason that Kontakt’s 16 output version appears rather than the stereo output version is because the stereo version would be pretty much useless in Dorico. If you use the stereo output version, you only then get two faders to balance all of the sounds available in your instance of Kontakt in Dorico’s Mixer, which would force you to do all of the mixing directly in Kontakt’s UI instead, which wouldn’t make much sense.