Set the CPE210 to client mode and connect it wirelessly to the RE210 if this is already connected to your local WiFi network. Connect your CCTV cameras to the CPE210 - no router necessary. The CPE210 has two ethernet ports you can use for your cameras.

If you use the RE210 as stand-alone device (not connected to a local WiFi network), it takes over the role of the client. In this case you will need a router, but the CPE can do this, too. In this case, set it to AP client router mode. The RE210 will be on the WAN side, the cams on the LAN. Use static IPs and set a static route on your laptop pointing to the cam network.

See the CPE user's manual, chapter Operation Modes for more ideas how to achieve what you want.