In situations like this, I think the person at the top of the chain that told employees to perform the illegal installations should be arrested and charged. On top of that, the company should be fined into bankruptcy. If the directors knew about it any companies they're involved with shouldn't be allowed to conduct future business in the municipality (or state).
Solves the “too big to fail” problem as the company continues to exist, the ceo ends up in jail and the owners end up broke, but the work still gets done.