The most common way to execute a macro on only one controller is to use different macro names for each site. This way the macro names don't collide when DTMF is decoded by multiple controllers.
For example, you can have control macros to enable and disable transmitters. You could make the first two digits of the macro name unique and keep the last two digits the same. So the Enable Transmitter macro could be named 8801 on one controller and 7701 on another. The Disable Transmitter macro could be named 8800 on one controller and 7700 on another.
The same with passwords. Each controller needs a unique password so when you are entering commands via DTMF that might be heard by multiple controllers, only one controller decodes the command. Other controllers ignore the command.
For example, by using password 1234 on one controller and 4321 on a second controller, a command that starts with a password will only be decoded by one controller.