Playdtmf and dictate

I am developing an control application driven through a web interface. The users will NOT have any connection to the system other than this interface and a headset (no keypad).

When I am using the dictate app through AMI, I need to control the dictation app using playdtmf. However, while I hear the DTMF tone in the headset, the dictation app does not. The result is I have no control over the app.

I have surmised that the DTMF signal is not available to any party to the call other than the specified channel (the extension). Is there a way to specify channel differently so the DTMF signal is sent to the dictate app rather than the extension?