You changed the name of the way to indicate the difficulty, I do not think that this should be done. The difficulty of the via ferrata is given in the key via_ferrata_scale=* (here, only on one of the ways of the relation because the others are just paths leading from and to the via ferrata). We do not want the same information in multiple places – this has the risk of one being changed and not the other, giving conflicting information. 

Also, had you wanted to change the name of the via ferrata, you should have changed the name of the relation as well as all five members. 