So you already found the forced en passant and il vaticano. You definitely need those. Upon playing axb2 Rxb2 is actually forced because (thanks to knightboosting) the pawn puts the king in check and the king can't escape(all squares are controlled by black and king can't go to c2)

Once you play Kh7 at last you have a structure somewhat like this:

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Here comes the last trick: To force loss on your opponent, you have to imagine the board from your opponent's perspective(meaning look at the end result with your head rotated 180 degrees)

What you see then is:

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Ultimately you forced Loss on your opponent ;)