I voted 'other', but mine is not an informed opinion.
I don't care if italiano is Italian, Australian or Eritrean. I don't care who he really is, but he clearly doesn't want us to know. As with others on this board, for that reason, even if I did know his identity, I wouldn't advertise it.
But speculation in ignorance is invited, so here goes...
The quoted post you gave, Thunder, spelt 'tumor', not 'tumour', so he might be an American/Canadian/Victorian, or the automatic spell-checker has stuffed it up, but he is less likely to be English.
But his signature quote is from Damian Grammaticus, who is (I believe) a BBC journalist. I think unlikely to American on that score, more likely to be English or Commonwealth.
Certainly a native English speaker, even if he does speak Italian. Australian would fit all of the above.
Clearly a DP refugee, but there are many others here.
More pertinently, however... so what?
His posts are occasionally frustrating because the attempts to feign a lack of command of English can result in the post being unintelligible. But just because he hides from one anonymous handle under cover of another is no crime. I'd be interested to know what the handles of the DPF refugees here are, just because that'd be interesting, but they have their reasons for not disclosing them. That's their choice, not mine, and if italiano feels the need deliberately to sound like Papa Giuseppe, let him.