You are 100% right…except your aren't.
We have a secured internal network, what I am proposing is taking a spare public IP on my backup internet connection, and having it only accept packets going to that port, and forwarded to the internal LAN to forward it to the IP in the cloud.
The system is in the cloud, however they won't open external ports on their firewall, which is annoying. We generally like the idea of using the VPN to keep things secure, but our employees are....dumb, and instead of hitting the giant button that says "reconnect" if it loses cell reception, they just complain it doesnt work, and then we end up losing the ability to track our fleet.
Sorry for the confusion, you are generally right, however we are taking every precaution to secure the situation