Guys,
Just a little request to help with clarity, can you please, individually, create a new post? I’m fairly competent with this sort of thing as I work in a similar field and have double NAT at home; so the struggles you’re facing, I’m likely to have worked through. The issue is, it’s difficult to work through individuals with similar-but-different problems. If you create a new thread, myself and others can try and help you work through them. You all, almost definitely, have different router/firewall/network configurations and it could be any number of issues with them all.
The main thing I’d say in the mean time is, ensure your routers/firewalls have logging enabled to a fairly high level so we can track packets through your network.
I’m UK based, so I’m off to bed now (0200 in the morning), but happy to help when I get up (probably 8 hours or so).
Just PLEASE create individual posts! At least from my perspective it’ll help with fault finding.