My nvr has died. Swann SWNVK-873004-US, 8 Channel 3MP w/ 2TB NVR & 4 x 3MP Cameras. I won't be able to access or rewire the poe cameras so I'm looking at a GW 4108EP. What I don't know is whether the installed Swann cameras will work with the GW nvr. I would appreciate any advices. I do not know if the Swann cameras are ONVIF.