It does leave the question of "what happens to the Papal States if they somehow own Malta and yet are overthrown in Rome" since I doubt the Great Powers will just let Italy seize Malta.They probably would if the UK doesn't take it. And the Pope most likely would still stay in Rome because he is still the Bishop of Rome (the Pope is the Pope because he is the Bishop of Rome), and also because leaving would most likely be seen as recognition of the Italian invasion and annexation, which the Pope OTL refused to recognize until 1929.