Immediate thoughts:
1. The "picture" is pretty clearly an illustration. It'll be hard to impossible to convince the audience that what they're looking at is a photograph.
2. The creature here is pretty overpowered: covered in unbreakable scales, able to eat ships whole, basically unstoppable. The fact that it, on top of that, also (probably?) makes people crazy is just overkill. I think it'd definitely be better if there was some kind of real vulnerability here OR a more active backstory.
3. The addenda are pretty pointless, all in all. The description covers "big sea creature", "makes you super scared of it", and "eats ships"; your first two addenda show a big sea creature making people super scared of it and a big sea creature eating a ship, respectively. They don't add anything. The third one makes the connection between this and the Julia event, but because you basically just a) mention that the Julia even happened and then b) immediately redact the thing that you add to the description of that event, it still doesn't contribute much to the experience.
tl;dr: The entity itself is overpowered, and everything after the description fails to contribute significantly to the article. B is solvable by removing the addenda, then solving A (making the creature more relatable, adding a backstory, etc.), and then, if you still want addenda, basing the addenda on exploring some not-yet-seen aspect of the creature.