By "work in how you found the signal", do you mean writing out some manner of intro about how exactly he ran into it in his universe? I could but I feel it'd just wind up being an overlong post that cuts the flow of the current events. Leo doing some short exposition on it to the crew if it comes up feels like a better idea. Especially since it's not much of a story, he was sent to scout a signal coming from an empty part of space, blacked out and woke up wherever he is right now. That's about how he'd tell it as well.