I'm not sure of what you're trying to explain .. first of all . your not in the rigth forum ..
It looks like you used Auto-Registration for all phone on oyour network .
If so, In auto-registration, the phone will use the device pool .. that is specified in "System | Device Defaults". Usualy, in a basic installation, this this still the "Default" Device Pool .
So, I thing you must take a look, is .. with wich CallManader Group .. the Device Defaults Device Pool is associated .
Take a look at this CallManager Group (System | CallManager Group) . You should have your both server in "Selected Cisco CallManager....."
About the usage of Auto-Registration feature ... personnaly : give the "most restricted" access is my guideline. The things is ... keep an eyes of what happen on the network .. and prevent outsiders to connect .. and start to use your net for toll fraud .
But, this still my opinion .
Martin