I got it working, watching the training video for SL2100 remote IP helped, same steps...

I had to add the local area network to 10-58 (networks to exclude from NAT). I also forgot to set all IP phone for NAT plug-and-play in 15-05. Not sure why the phones on the same LAN as the SV9100 would be set for NAT plug/play but its working. Now the local phones are ok and the remote IPT registered and works.