External Connection Issue using TS Web Access

I am attempting to impliment a Terminal Server for external users and am having an issue with external access.  I am able to get to the TS Web and log into the site.  Remote Desktop Tab has been removed from Web Access so I can see the RemoteApp Programs and Configuration Tabs.  When launching an associated software I first get a warning that the publisher of the remote app cannot be identified after selecting "Connect" I get an error stating "The remote computer could not be found.  Please contact your Helpdesk about this error."  As mentioned this is ONLY happening externally and happens while connected via VPN as well.  I can take the same non-domained laptop into the office and connect without issue.

I would seem to me that this is some type of firewall issue or permissions issue while connecting outside of the office.  But obviously I am asking the question so may be completely clueless as well.. lol...  I have done the following.

1) verified https and rdp ports open to the TS on the firewall and all NAT looks correct.  I can rdp to the external ip and connect to the server in question.
2) worked through all settings as per Microsoft publication and rechecked - again all is as published.
3) read articles on EE as well on the net without much luck and tried suggested fixes with TS RemoteApp Manager and TS Gateway

The server on the domain is server.domain.net and externally resolving from https://tsserver.externaldomain.com/ts so I am also wondering if there is an issue there as well.

I am still only using a self signed cert as I am in the testing stage right now.  
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