What I ended up doing was taking 3 teeny shot glasses and using them to prop up the tray above the level of the notch. Looked a bit odd but probably better than a pie tray. Smoked smooth like butter haha.
Wow, that's odd, never seen a KM tray not actually fit on a KM. I have the two tier, two hose version of that same one and my tray fits fine. That's really strange. =\
You could always just use a disposable pie tray from walmart for now. It'll look like shit, but you can smoke that beauty indoors until you get a new tray.