Figured it out.
Had nothing to do with the internal / external IP.
It had to do with the WWWRoot on mahara autodetecting as domain.local instead of domain.org because the hostname of the box was domain.local.
So I edited the /var/www/mahara/config.php file and changed
//$cfg->wwwroot = 'http://domain.local/mahara/';
$cfg->wwwroot = 'http://domain.org/mahara/';
After that MNET broke due to the SSL key being set to the domain.local, so I had to go into mysql and run the command
I then went back to the networking page in mahara and it regenerated the SSL key.
From there I went back to moodle and under networking / peers i added the peer using the correct wwwroot. set the services, saved, and deleted the old one.
whew. Thankfully this is a new setup so nobody was using mahara at all.
Hopefully if anybody runs into the same thing as me the above will help them.