i can never find my friends server, but i have all the filters n stuff turned off!

It seems like your friend's server doesn't register with the lobby server. Tell him to make sure that there's nothing blocking the ports Soldat uses (this can be a firewall, router or similiar)

From the manual:

Game Ports

Important! - If you have a firewall you should open the UDP game ports
default: 23073 for the server (can be changed in Soldat Setup) , client uses a default port: 23083 (can't be changed)
There is an option to join firewall servers without opening the ports, but only through the lobby server (through the server list - forwarding).

The Soldat server uses the following ports:
UDP: game port (default 23073)
TCP/IP: admin port = game port (default 23073)
TCP/IP: files port = game port + 10 (default 23083)

the "in-game" lobby also has issus displaying all of the games that are really registered in the lobby, although i've never known for sure why this is

Could also be your version. I just reinstalled Soldat yesterday that I've had on my harddrive since earlier this year and couldn't figure out why I couldn't see my bf's server, and why I only had 15 servers displaying and he had 80. Tried his IP and the game said I didn't have the right version so I had to update.

As FLAB said, there is a bug in the game where it sometimes doesn't display the servers properly although it's in the lobby. I have dealt with this problem since the early days of soldat and it's still an issue for me now, sometimes you see the hidden server if you make your filter more specific.

Make sure his "Register to Lobby" is checked when he makes the server.