It's relevant because, IMO, he's wearing the same striped epaulettes as the captain, therefore acting as captain. That would put him in charge of the operation, giving him access to boats, keys, supplies, etc.
We'll just have to wait & see if any of that is true and if it has anything to do with the case. I have problems with the idea that a 26 year old guy who has a 3 year old kid would be buddying around with 17 & 18 year olds, much less be willing to stick his neck out for them. Seems just weird to me but then weirder things have happened.