My problem seems to be resolved. The tutorial I followed had me putting my settings in eqemulogin.ini. I debugged the problem to the point where I found out that the world server was always being told that the client was local, never external. I got the latest code for eqemuloginserver and compiled it, which led me to actually populating login.ini (I didn't ever use that before), which contains the "local_network" setting. Once I set that and used my newly compiled eqemuloginserver.exe, the system ran perfectly and properly evaluated me as internal/external depending on where I am logging in from.
The solution of putting your external IP in <address> and <localaddress> in eqemu_config.xml would probably work fine for people using the precompiled eqemuloginserver.exe and the tutorial that only has you set up eqemulogin.ini (not login.ini) but for me, I suspect I had an issue with my router being older, as my local client, when given the external ip, disconnected every 2 minutes. I think my router was getting confused.