Hard to say why it is not working. My suggestion would be to connect it directly to the autopilot first and get a connection, then when that works, move to making he bridge to 915MHz. The other option is to connect a FDTI cabel and terminal to the serial port, and then connect using a computer and then telnet to the ip address and port. You should be able to send characters back and forth between the terminal connected to the serial port (via FTDI) and telnet.
To connect via FTDI
screen /dev/cu.cu.usbserial-A1024NRG 57600
To connect via Telnet
telnet 192.168.1.1 2000
If you are still stuck, maybe we can do a quick text chat on gitter or Skype.
