I would assume the ocean would just shredd something so flimsy to pieces even with normal wave action, let alone a major storm. If you want something to survive 2-3 months in the ocean it needs to be quite sturdy.
It's hard enough sometimes for normal companies to find the right resources. How many engineers are willing to work for cartels? Either they can do that by means of threat or fear, or finding the least ethically minded engineers that are looking for lots of money. I bet both cases are difficult to manage.
I think the cartels have already solved this problem in another area:
"Cartels have kidnapped technicians doing maintenance on cellular towers to make them fix their networks, people working in the sector said. The technicians usually are released after a few days, if not sooner."
