I'm sure that there is one out there,or one that could be built.
A thought might be ,from experience and talking to a lot of other cooks,to stick with independent units.
If you have a problem with this multiple/master unit,while on the road,you could be in dire straits.
You can find sales on Amazon,etc ,where you can get four for three and get free shipping, on units like a Taylor.
Makes the unit price less than $10.
Maybe buy a Maverick,and a couple of Taylors,and still get free shipping.
Many of us have a Maverick,cordless remote,so it will alert us for large increases,or decreases in cooker temp ,while we sleep in the truck,or trailer.[ or at home in bed ,during the pouring rain]
Of course many of us FEC cooks set it up and go to the motel until morning at contests.
Many won't probe their large meats,until early morning,and then usually check doneness with an instaread.
I don't know of a time that I would have moved large meats around, because of a minor "hotspot" in an FEC.
Now a wired remote in your butts,and another in briskets can be handy.
The nice thing about a $10 Taylor,is if you crimp a probe,drop the reading unit off the truck,while driving across the parking lot,drop the reading unit in the dishwater and can't find it in the dark,etc,you just get another out of your kit and stick it in.
Now personally,reading the ambient temp would only be useful if you were concerned about a hard freeze,and maybe your water hose freezing up.
The $10 remotes will give you current internals,and alarm when a target temp is reached.
Just my $0.02