I am confused on how you operate with two routers, but OK. I would suggest trying to reconfigure your SB by programming whichever router you plan to plug the SB into with an ethernet cable to first assign a static IP address to the SB, then program that router to forward port 5001 to the static IP address you have assigned to the SB, then plug in the ethernet cable, reboot that router and reboot the SB, and then see if they will connect up.
Then visit your account at support.slingbox.com and see what it says about the Internet setup status of your SB.
What I understand from your post, is that you're having problems trying to connect the Slingbox to the network.
In this case, what I would recommend is to check the following links: