I'm guessing Allmon3 requires commands to be run via rpt fun..., since that's the example provided in documentation. However, that prevents dynamic arguments from being passed from Allmon3, as shown above.
Allmon3 connects excluslively to Asterisk/AMI by design. Any command you can run via Asterisk is supported. But you cannot make an arbitrary shell call, no.
If my recent open issue with CoreShowChannels with node number in CallerID is resolved, which is looking promising, I'll look into possibly adding this to the Allmon3 code. It is mostly AMI calls and logic in the script anyway.
You mean you're going to add the capability to do what you want into Asterisk commands? Allmon3 can't run any system commands because it runs as an unprivleged random user.