I can make calls from extension. I don't think it is a firewall issue.
The following is a CLI transcript from my last attempt starting from when I the agent was connected to the conference.
[Nov 20 14:24:23] > Channel SIP/202-00000017 was answered.
[Nov 20 14:24:23] -- Executing [8600051@default:1] MeetMe("SIP/202-00000017", "8600051|F") in new stack
[Nov 20 14:24:23] == Parsing '/etc/asterisk/meetme.conf': [Nov 20 14:24:23] Found
[Nov 20 14:24:23] == Parsing '/etc/asterisk/meetme-vicidial.conf': [Nov 20 14:24:23] Found
[Nov 20 14:24:23] -- Created MeetMe conference 1023 for conference '8600051'
[Nov 20 14:24:23] -- <SIP/202-00000017> Playing 'conf-onlyperson' (language 'en')
[Nov 20 14:24:24] NOTICE[28319]: rtp.c:849 process_rfc3389: Comfort noise support incomplete in Asterisk (RFC 3389). Please turn off on client if possible. Client IP: 192.168.1.26
[Nov 20 14:24:25] == Manager 'sendcron' logged off from 127.0.0.1
[Nov 20 14:24:46] == Parsing '/etc/asterisk/manager.conf': [Nov 20 14:24:46] Found
[Nov 20 14:24:46] == Manager 'sendcron' logged on from 127.0.0.1
[Nov 20 14:24:46] -- Executing [915127626397@default:1] AGI("Local/915127626397@default-3a20,2", "agi://127.0.0.1:4577/call_log") in new stack
[Nov 20 14:24:46] -- AGI Script
agi://127.0.0.1:4577/call_log completed, returning 0
[Nov 20 14:24:46] -- Executing [915127626397@default:2] Dial("Local/915127626397@default-3a20,2", "SIP/15127626397@did.voip.les.net||tTo") in new stack
[Nov 20 14:24:46] -- Called
15127626397@did.voip.les.net [Nov 20 14:24:50] -- SIP/did.voip.les.net-00000018 is ringing
[Nov 20 14:24:50] -- SIP/did.voip.les.net-00000018 is making progress passing it to Local/915127626397@default-3a20,2
[Nov 20 14:25:00] -- SIP/did.voip.les.net-00000018 answered Local/915127626397@default-3a20,2
[Nov 20 14:25:00] > Channel Local/915127626397@default-3a20,1 was answered.
[Nov 20 14:25:00] -- Executing [8366@default:1] Playback("Local/915127626397@default-3a20,1", "sip-silence") in new stack
[Nov 20 14:25:00] -- <Local/915127626397@default-3a20,1> Playing 'sip-silence' (language 'en')
[Nov 20 14:25:00] WARNING[28373]: file.c:1297 waitstream_core: Unexpected control subclass '-1'
[Nov 20 14:25:00] -- Executing [8366@default:2] AGI("Local/915127626397@default-3a20,1", "agi://127.0.0.1:4577/call_log") in new stack
[Nov 20 14:25:00] -- AGI Script
agi://127.0.0.1:4577/call_log completed, returning 0
[Nov 20 14:25:00] -- Executing [8366@default:3] AGI("Local/915127626397@default-3a20,1", "agi-VDAD_ALL_outbound.agi|SURVEYCAMP-----LB") in new stack
[Nov 20 14:25:00] -- Launched AGI Script /var/lib/asterisk/agi-bin/agi-VDAD_ALL_outbound.agi
[Nov 20 14:25:02] == Parsing '/etc/asterisk/manager.conf': [Nov 20 14:25:02] Found
[Nov 20 14:25:02] == Manager 'sendcron' logged on from 127.0.0.1
[Nov 20 14:25:02] == Parsing '/etc/asterisk/manager.conf': [Nov 20 14:25:02] Found
[Nov 20 14:25:02] == Manager 'sendcron' logged on from 127.0.0.1
[Nov 20 14:25:02] == Manager 'sendcron' logged off from 127.0.0.1
[Nov 20 14:25:02] -- AGI Script agi-VDAD_ALL_outbound.agi completed, returning 0
[Nov 20 14:25:02] -- Executing [8366@default:4] AGI("Local/915127626397@default-3a20,1", "agi-VDAD_ALL_outbound.agi|SURVEYCAMP-----LB") in new stack
[Nov 20 14:25:02] -- Launched AGI Script /var/lib/asterisk/agi-bin/agi-VDAD_ALL_outbound.agi
[Nov 20 14:25:02] == Manager 'sendcron' logged off from 127.0.0.1
[Nov 20 14:25:02] == Manager 'sendcron' logged off from 127.0.0.1
[Nov 20 14:25:03] -- AGI Script agi-VDAD_ALL_outbound.agi completed, returning 0
[Nov 20 14:25:03] -- Executing [8366@default:5] Hangup("Local/915127626397@default-3a20,1", "") in new stack
[Nov 20 14:25:03] == Spawn extension (default, 8366, 5) exited non-zero on 'Local/915127626397@default-3a20,1'
[Nov 20 14:25:03] -- Executing [h@default:1] DeadAGI("Local/915127626397@default-3a20,1", "agi://127.0.0.1:4577/call_log--HVcauses--PRI-----NODEBUG-----16---------------") in new stack
[Nov 20 14:25:04] -- AGI Script
agi://127.0.0.1:4577/call_log--HVcauses ... ---------- completed, returning 0
[Nov 20 14:25:04] -- Executing [h@default:1] DeadAGI("Local/915127626397@default-3a20,2", "agi://127.0.0.1:4577/call_log--HVcauses--PRI-----NODEBUG-----16-----ANSWER-----18-----4") in new stack
[Nov 20 14:25:05] -- AGI Script
agi://127.0.0.1:4577/call_log--HVcauses ... --18-----4 completed, returning 0
[Nov 20 14:25:05] == Spawn extension (default, 915127626397, 2) exited non-zero on 'Local/915127626397@default-3a20,2'
[Nov 20 14:25:07] == Parsing '/etc/asterisk/manager.conf': [Nov 20 14:25:07] Found
[Nov 20 14:25:07] == Manager 'sendcron' logged on from 127.0.0.1
[Nov 20 14:25:07] == Manager 'sendcron' logged off from 127.0.0.1
Vicibox1*CLI>