this seems like an insurance problem, rather than a technical one. rogue waves appear to be rare enough that spending money on prediction or detection might outweigh the cost of simply insuring against catastrophic loss
Tell that to the people on the ship that it happens to!
Granted, it's usually survivable. Decades ago a friend of mine on a containership experienced a rogue wave with no more harm than being terrified by "either the last thing I was ever going to see or the most majestic thing I'd ever see" but it doesn't always end that way.
Ships used to be built to the largest waves that were conceivable. We underestimated the forces in a rogue wave by a factor of more than 5. Ships today are built stronger, we are careful about seas where rogue waves are more common, and insurance now knows to take rogue waves into account in their policies.
