One step at a time.
We just covered the agent logging in and hearing "You are the only person in this conference". Then the agent presses "Resume" and does NOT hang up the phone.
At this moment, you should be watching the asterisk CLI (available via "asterisk -R" in the ssh console). I mean at the moment that the agent presses "Resume".
Right then: Does the system initiate a phone call outbound? (Please show the output from that moment ... or the next 2 or 3 seconds at most, until the "Hangup" line if there is a call).
For this to work, you'll need to have a Campaign set up with a list assigned and leads in the list, etc. Just seeing where we are.