I've been working a lot with private libs and this one has stumped me.
THe way true tone overriding works is on the Info.plist as defined at https://developer.apple.com/library/content/documentation/General/Reference/InfoPlistKeyReference/Articles/iPhoneOSKeys.html#//apple_ref/doc/uid/TP40009252-SW31
I want to be able to make it so I can change this during the runtime (sometimes i notice flickers of true tone turning off which is probably an iOS issue)