All, I’ve resolved my issue — sharing what I did in case it helps the OP or anyone else running into something similar.
My troubleshooting showed the problem was isolated to my Wi-Fi network since the cam worked fine on a different one. My router is provided by my ISP, and most settings were locked down, so I couldn’t change much myself. The only thing I initially had access to was disabling either the 2.4 GHz or 5 GHz band. I tried disabling 5 GHz and forcing both my phone and the cam to use 2.4 GHz, but that didn’t work.
I then called my ISP and asked them to give me access to the modem interface so I could adjust some settings. I even preemptively ordered my own router in case they refused. Luckily, they agreed, pushed an update to the modem, and within minutes I had full control.
I tried a bunch of things — adjusting WPA security settings, changing the network name and password, even disabling WPA entirely so the network was open. Still no luck.
What finally worked was splitting the bands. Instead of one blended 2.4/5 GHz network, I set up two separate networks with the same password but slightly different SSIDs. Once I did that, the cam connected right away.
Out of curiosity, I switched the network back to a blended 2.4/5 GHz setup — and, as expected, the cam dropped offline. To fix that, I kept the cam paired to my account and pressed the setup button on the bottom to initiate the setup process again. Since the cam was already paired, it just reconnected to the blended network without any issues.
So now everything’s back to my original blended 2.4/5 GHz network, and the cam works perfectly. I still don’t know why a power outage caused this or why splitting the bands was the key to getting it reconnected, but if anyone else is stuck, this might be worth a try.