Those breakers are hard to trip. They wind up for a second or two before they pop on a short.... (so I've seen)
Hammer in metal nmd staples to those back 2x4s (or where you can) and use white zip-ties to secure the wires. Good for tight spots..
look low, and if it's nippled through to the meter, then that's where it stays. But the sub panel looks movable... You could move it right out of there
You could try getting them to spring for a matching panel, if they are worried about it.