Let's be clear: there is no chance that a referendum chooses union with Italy, not if it is a fair one. There is a vocal minority of irredentists, financed obviously by Italy, but the majority of the population wouldn't care to go that way (unless there was the risk of a German occupation, but this is virtually impossible without an alliance with Italy).
I don't see either why the (unstable) committee that governs Italy would care to take such a risk. Corsica isn't worth a damn, and even among the irredentist claims was probably the least serious.
Tunisia and Djibouti would be worthwhile pieces of real estate, however, and I would believe that France could be intimidated enough to accept the Italian requests.