I suspect that after the backend server meltdown the method used to determine and also access the updates has most likely been closed?
The bot was a God send as the actual BI updates web page most times always seems to be out of sync when compare to the latest actual update available via the BI...
Agree that 100% usage is a bit extreme but if all the cams are enabled then maybe it’s using resources to try and establish contact.
Try disabling all the cams and see if it behaves any differently.
If your support has expired make sure you have a version of the update that was released at or before the expiry date else your system will go into eval mode.
What routes between the 2 networks?
As suggested do the required to set up tailscale and see what happens. I use TS and it is just about the easiest thing to setup and get working.
Here in the UK I had what I think was a Sparrowhawk rip a pigeon apart, no footage as this was before my cams. Recently I had a crow go after a sick pigeon eventually killing it, I think I have footage of that somewhere, will post it if I find it.