repairing a hump in the wood

The tub was delivered yesterday.
Thank you ever so much for everything again.
We, however, made a few mistakes and I would like therefore to ask you for some additional advice.
First of all, we forgot to read the paper attached to the plastic cover of the tub (we were so excited, like little kids, to open our present !!!), we realised afterwards that we should have left it wrapped in, since the bathroom is not yet ready. What should we do (humidity level, dust etc.) ?
Also, there was a small accident while opening the crate. The damage I mentioned to you on the phone was only on the crate, and there was no trace of damage on the tub itself, so that is resolved. However, we used a hammer to loosen the side boards of the crate, and the hammer must have rebounced and hit the top edge of the tub on both sides, at the height of the brand. I’ll send you the pictures when I get them on my computer from my neighbour. That means that we will probably have to sand down the whole top of the tub all around to make the marks disappear. Is that the right thing to do ? Are there special instruction for that matter as far as making the slanted edge, and/or treating the wood once sanded ? Is the wood treated, or is it only treated at the bottom ?
Everything would have been perfect, were it not for our impatience and uneducated use of that hammer…
With my warmest regards,

Please note:
1) for the plastic wrap, if it is still usable, wrap again the tub and use generously wide tape to seal the openings
If the wrap is badly damaged, you should get some new one from a home center. Close with tape.

2) For the hammer marks: I will need to see the pictures.
Wood swells when it is wet and there is the possibility that it slightly returns back if you blot it with a wet cloth (not just dump, make it dripping wet) or by pouring water on it for at least 1 hour.
If the wood is not returning, you can apply the dump cloth on the damaged area and press it with an iron (cotton-high temperature, apply intermittently for few seconds).

A third option is to sand it. The wood is not treated (excepted for for the bottom plank head). I think you should be able to sand only the faces which are damaged and not the whole top.
The corner fillet (mentori) should be made with a hand plane but this tool is difficult to use. You may employ a sander but be aware that the corner will become roundish instead.