Talentwise he's miles ahead of the Stendardo's and Knezevic's of this world. He's backup for the moment but he's a more sensible investment than the two aforementioned.
So, yes he's cover, but no, I don't think there's no intention to buy him whatsoever. Let's see how it goes from here.
No. Apparently he's a doctor and therefore might be able to help with our injuries. That doesn't seem to be something Juve look for when hiring medical staff.
in all honesty i cannot see Canna playing every game this season and once the games start coming think and fast i see Caceras as becoming an important member of the squad