While the 88mm gun was one of the best heavy AA guns the mounting on the Tiger was not desinged to be used in the AA role. The treverse would be too slow, the sights wrong and the elevation too limited and the I doubt that AA ammo was ever issued to Tiger units.
Being shot down by tank main guns might have happened in very rare instances but this was more a case of luck than judgement. The super-ack tanks in il2 are one of it's worst features and and I'd hate to see them happen here.