It's ICMP type 3, code 9, described in section 188.8.131.52 in http://www.ietf.org/rfc/rfc1122.txt
I'm having no such issues on my RB433 I use at home.
At least if no one knows nothing, say so.
That's ridiculous. I get that you're desperately looking for help, but there are thousands of users on this forum. You cannot expect all of them to drop you a line here saying "hey, just to let you know: no idea how to fix your problem". If no one posts, no one knows.
Have you contacted the official support channel at firstname.lastname@example.org
Specific answers require specific questions. When in doubt, post the output of "/ip address print detail", "/ip route print detail", "/interface print detail", "/ip firewall export", and an accurate network diagram.