Don't have an AQ,and never tried a crown roast in any of the smokers.
I guess you'd cook it on a sheet pan to save the juices?
They are typically stuffed and the stuffing can dominate the internal cooking temp of the whole dish.
I believe I'd make my stuffing without any eggs,raw meats,etc.
I usually cook pork loin 335*-350*,so I'd probably run the AQ hot.
I might warm the stuffing to about 125* in the house oven,and hold it until the pork is around the same mark and then add the stuffing to the roast.
I always brine today's superlean pork loins,and that will also give some cushion to the pork.
Bring the pork up to about 145*,pull and hold the whole dish under foil.
Let it rest 1/2 hr,while you make gravy,etc.
Being cautious,I'd try to do a practice one,before doing one for a large group of strangers.
Good luck and let us know how it goes.