This was before you made the latest changes to registration / authentication.
I suggest that you undo those and we troubleshoot the problem above.
Taking the Warning header at face value, it seems to be related to an obscure setting in the HT “Check SIP User ID for Incoming INVITE”. But this defaults to No and you would have had no reason to set it. Did you configure a used device without first doing a factory reset?
If this is not your issue (the setting is indeed No), try setting From User in the trunk to the same value you have for Trunk Name (which I assume is what you redacted to xxxxxxx7300).