It is difficult to tell from the pictures. I don't know what the weight distribution is on a Sealegs, but the axles on the trailer look to be a long way forward, possibly in the middle of the trailer. If the Sealegs is very tail heavy, it would make the trailer very twitchy and prone to snaking. The LR Hi Cap being a pickup, is light on the tail as well. When towing with defenders, I like to have the trailer nose heavy as it tows so much better and safer. If the trailer setup is not correct for the Sealegs, that may have contributed to the accident?