I did a tcpdump as you suggested (a tool I was unaware of until now! very useful, thanks for the tip).
I was unable to successfully copy the file to my local machine from the remote server in order to use wireshark to analyze but did take a look at the raw file in vi on the server, it looks like I am getting traffic into the server when I place a call, however I am getting an unauthorized error, and it looks as though its my SIP provider that is throwing the error.
Here is the entry that caught my attention (scrubbed of any personal info):
SIP/2.0 *** Unauthorized
Via: SIP/2.0/UDP SIP_Provider_IP:5060;branch=&& ;received=SIP_Provider_IP
Via: SIP/2.0/UDP SIP_Provider_IP:5060;received=SIP_Provider_IP;branch=&&;rport=5060
From: “Unavailable” <sip:INCOMING PTSN NUMBER@SIP_Provider_IP>;tag=&&&&
To: <sip:MY VoIP PHONE NUMBER for asterisk@AWS Static IP>;tag=$$$$
CSeq: 102 INVITE
Server: Asterisk PBX certified/13.21-cert6
Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER, SUBSCRIBE, NOTIFY, INFO, PUBLISH, MESSAGE
Supported: replaces, timer
WWW-Authenticate: Digest algorithm=MD5, realm=“asterisk”, nonce=“5006798e”
Is this enough information to determine if this is my configuration settings in asterisk or with my SIP provider?
Thanks again for the help!