That depends on how you connected the 2nd router. If you connected the 2nd router to a LAN port then yes, it's on the same network. If you have connected the 2nd router via the WAN port, then the answer is no. In the 2nd scenario you will also be dealing with a 2nd NAT from the 2nd router. You'd have to open a port to get to the cameras in that case on the 2nd router.