Need help with RPC over HTTPS

Scenario: Have 2 offices jacksonville and Orlando. Exchange server is in Jacksonville and is called jagmail.jaguartechnologies.com and is at an IP address of 192.168.1.3, it's external internet FQDN is mail.jaguartechnologies.com and has  and external IP address of 72.158.123.99. I created a dns record internally to point the mail.jaguartechnologies.com to it's outside IP address. There is an active directory server and DNS integrated AD at both locations.

Right now Outlook clients in Orlando are connecting behind a VPN from a 192.168.31.x subnet to the 192.168.1.3 subnet to download emails in caching mode. Works great MOST OF THE TIME, but they have had some problems with the VPN occasionally locking up. When vpn is down - no email . BAD.

So, I thought - lets put a wildcard SSL Cert and have them connect via RPC over HTTP. Works externally great pointing to mail.jaguartechnologies.com. Works internally great pointing to the external mail.jaguartechnologies.com address  in orlando when the VPN is up, but if the VPN is down it does not. It is almost as if AD or something is still pushing it over the internal address maybe because AD is down there? not sure why.

But it is hosing me up. The other scenario is users who float in and out of the office it needs to work inside and outside the office, not sure it will.