Large Angels or most Angels for that matter have been known to pick at Sharks/Rays. I would imagine most of the triggers might except ones like Blue Throats and Sargassums but I am basing that off info from RC. I would be most concerned of the shark lying on the lionfish depending on if it is on a rock or not. If you haven't read the book " Aquarium Sharks and Rays" by Scott Michaels, you ought to if this is your first shark. Has great info about keeping sharks and rays. That book and info from the fish keepers on this site will help you out a bunch. Also, one thing most people don't realize about Brown Banded Sharks,(this is assuming it is a typical Brown Banded), is they can reach in excess of 4 feet in length so if you are putting it in a standard 180, you might be upgrading or looking to find someone who can house it when it becomes an older adult. Just info. Not sure of your experience with this species. Hope this helps. I am sure other people will chime in.
Jim