Adding an entry (or removing it) from ASTDB does not trigger an AMI event in Asterisk. FOP2 relies on those events to show status. If there is no event being fired via AMI there is no way to track real time status changes. With the FreePBX integration, what FOP2 does is inject some actions into the regular FreePBX feature codes so it fires an event via the UserEvent application, that FOP2 can understand to reflect the status change. So, in order to see if there is any AMI event broadcasted when you set/unset DND in your phone, you can start fop2_server with debug level set to 1, that will show only the AMI events. Something like this:
service fop2 stop
cd /usr/local/fop2
script capture.log
./fop2_server -X 1
AT this point log into FOP2 to see the panel, then try setting/unsetting DND with your phone, look at the screen to see if there is any related event when you press the button. Then
ctrl-C
exit
service fop2 start
AT this point you have the capture.log file to inspect in more detail if you want.. I do not know about DPMA and how it works.. if it talks directly to Asterisk with no way to alter behaviour, and it only sets/unset an astdb entry, then I guess you won't be seeing a related event reflecting that status change, making real time monitoring of that state just not possible.
Best regards,