The way its SUPPOSED to work, is you open an item not as described, and you return the item.

The problem is, you messed with the blade after the fact. Once you spotted the crack, it should have gone right into the box for returning. There is now an obvious breakage which was not there before, and it would be within the sellers rights to deny your return. A hard to see crack can still be sold as a display item collectable. Now the blade is simply a set of scales for a restorer to pick up for a few bucks.