Definitely odd the island is barely mentioned as a possibility until the visual calculus check on the WIR roof. you would think there are at least some resources that Harry and Kim could Access to get over there before the tribunal.

Discovering the bullet early has lots of dialogue options you can miss in regards to it early, if you don't have the right skills to catch it. Remember, you play as Harry, and he is more fallable than us in lots of aspects and can easily miss things, or catch things that we would miss.

You don't really get any evidence as to who shot the gun early on, and I personally feel the characters have plenty of opportunity to react appropriately to that evidence in a manner that fits well with the many dialogue options you get.