I struggled with VZB support for days without resolve to get my S5 to text outbound from mexico. Was able to receive text and call. I finally tried using the VZB message+ and can't believe that the tech support did not offer that suggestion after removing sim-card, check roaming, etc. etc.
One other note about this 'TRAVEL-PASS' feature, it does not work until you try/fail a few times in the morning for example, then you receive a text from VZB that it is activated,, even though it shows activated in your web-international travel in your account. A messy work around, as I had to go back to using the Android message first each morning, then get get message from VZB that Travel-Pass is activated for 24 hours, then go back and change to the VZB Message+,,, then works. I'm moving to ATT phone, as they are in-country for Mexico, and don't have these issues.