Remote access not working completely

Hi All

I have been called out to a job to help the second Electrician(level 1) figure out the problem. The first is gone. He was a level 2. I am a electrician and level 2 also.
I have not set foot on the job yet. I have the Ra2 files originally created in 6.?.? and converted to 6.3.0
System is 2 main repeaters, 114 devices.
Remote port is set to 51023
DHCP disabled on both

The problem I'm told is remote access. Here is the layout I'm getting.
App works fine on site. Remote is working, they can see the lights change on their cameras but the app is not showing any feed back.
The A/V guy did some changes previous to this problem but I have not been able to talk with him yet to get any ideas.
Before the changes all worked fine.
Will be on the job wed. Until then I'm flying in the dark.
Just trying to get some ideas before hand.
DNS problems, VPN, multicast.....?

Thanks for any help

Have the homeowner log out of their remote access account and then delete the system in the Lutron Home Control+ app. Next have the homeowner login to their remote access account. Select the system that now appears in the Lutron Home Control+ app. Do you still experience this issue?