How to Connect to C3000 Modem/Router in Bridge Mode

I'm hoping to view the log of a  C3000 Modem/Router which is set to Bridge Mode. I haven't been able to reach it from a laptop directly plugged into it at routerlogin.net, 192.168.0.1 (which was it's former IP), 192.168.100.1, or the public IP it has now.

For background, the C3000's log had been filled with endless "DoS Attack" entries that I gave up trying to stop, after finding several posts indicating it was a issue for which there was no fix. It wasn't clear that it was my network being attacked, but I was concerned that my C3000 had been made part of a botnet attacking others.

I bought a Ubiquiti Edgerouter and Unifi AP and set the C3000's "Router Mode" to "No".

I'd really like to see that the attack log entries have stopped, so a factory reset won't be a solution. Is there another way to reach it?

Thanks!