but from the local network on these domains to open the web interface Mikrotik
This is a KAG in General?
You have within the network domain should not lead to Mikrotik, and not on his external IPS and local IPS to the web server.
If this well does not have to open any web muzzle Mikrotik.
You are either in the hosts IPS Mikrotik tied to domains or what?
And that the sites were accessible from outside, then microtime need to traverse only 80 and 443 (if SSL) to the local address of the web server.
At the same time on the required domain users outside will be taken only if prescribed in the hosts matching domain to your external ip.
Well, or hang each domain in the web server on different ports and do port forwarding for each site separately, then the sites are accessible from the outside without a domain name, on ip with a clear indication of the port.
Going from local area will also have to specify the ports.