"Though I suspect another problem would be getting another ship large enough for all those cranes and strong enough to support all the weight close enough to the ship without them damaging each other by knocking into each other from waves and weight movement."

I don't thinks this is your concern. Desperate times, desperate measures. Likely you would fix/attach the crane ship to the container ship. I am sure they are willing to salvage two ships at this time. The daily losses must be gigantic.