Ultimately, it is up to the event organiser to determine wherever or not your weapon is safe for the arena it is being ran in. Telling them about your robot, especially when new to the scene (i.e. a new build) will help determine wherever it is safe for your robot to compete. In this context, photos of the way it is attached and the expected stats via a e-mail conversation or similar, as you've laid out, will help.

The tech check process, at the event itself, will also help determine if it is safe to run (noting that pre-approval doesn't override this - all robots have to pass tech check). Not at the same weight class but at the Antweight event I run, I have spinners demonstrate safe control in the arena during tech check itself. From memory, I think the last time I went to the BW Championship in 2019, I think the same thing happened there too.