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).
Fines need to increase with subsequent offenses, otherwise they become just a number in the cost of running business. If the fine is 100k, but the profit from breaking the law is 1M, then it makes more sense to keep breaking the law and keep paying the fine.
Instead the fine should increase every time. The first time it's easy to pay the 100k, but then it rises to 200k (still worth), 400k (not so much worth it), 800k (barely profitable), 1.6M (actual loss) and so on. Of course this only works if the fine keeps increasing faster than the profitability of the crime.