Hi and thanks for your help,
I forgot to tell it but, I had already tried this solution and … It throws errors, which seems normal since it has hidden sheets and Pivot Tables.
You can check this out : WorkBook Read Range: Index was out of range. Must be non-negative and less than the size of the collection.Parameter name: index - #9 by pakankshabha
Only way to manage today I found is by the method described
I think yours is a good approach, I recommend to try yor solutions first and, if it doesn’t work, mine 
Cheers