Good Morning,
I'm afraid that under the version of Maximizer you are running there is no way to do this.
You will need to get all your remote people to come into the office, process data on their remotes and then manually copy the packets into the appropriate inbox locations on the server. Then you will need to process packets on the server.
You will then need to change the IP address on the server and create new sites for all the remotes.
One the remotes themselves you will need to delete the MXZREM.MAX file from C:\Program Files\Maximizer\Max Exchange, this resets the Max Exchange removing all its settings. Then connect each remote up in turn.
I would strongly suggest you consider upgrading your Maximizer as Enterprise 2000 is an extremely old version and new versions of Max Exchange have the ability to store both a DNS name and an IP Address so you can avoid issues like this.