I have received an aamilet from Aamica for a Campaign, do I have to connect this aamilet to my Account?

No, you will not be able to connect these to any other Account. These aamilets are already connected to a separate Aamica owned Account & Favorite list associated with the Campaign. The connected Favorite list & aamilet pair have a Favorite list visibility set to Public, which will allow any other Account to access it via Aamica Connect.