My new gas range came with an anti-tip device, some kind of angle iron bracket that attached to the bottom front of the range that would stop it from tipping if someone leaned/climbed on the open door.
I have lived in Northen California most of my life and never seen or heard of stoves or fridges being chained to the wall. Water heaters, yes (strapped to wall, not chained), but not fridges or stoves. Even if they needed to be, straps would be used, not chains which collect grime. Maybe in a steampunk house they would use chains, lol.
I think it's too soon for that, unless the Ts have asked friends/family/property management company to do that (unlikely, IMO). Remember that legally they are still innocent until proven guilty, and the house is their property. Of course it's also a crime scene, and that probably takes precedence. I guess if it was declared a public health hazard they would have to do something though.
The power company would shut off power after a while of no payment but I would expect that to take a few months. IMO of course.
I hope you reinstall that clip to the back where it belongs. It's the back that lifts off the floor if too much weight is put on the open door.