Another kind of twist would have given this series a totally different atmosphere: The video could have been worse, like mostly showing the MC from behind, and there would have been another student, perhaps a year above, who'd normally look more or less something like the MC did back then. The girls would have misrecognised him as the helper, seeing how they were in panic back then and maybe couldn't really remember exactly what he looked like. The dude would falsely admit it. The girls would start to fawn on the faker. This could have continued for weeks until the sisters became disillusioned by the scammer, disappointed their mother's savior was basically just some nanpa bastard. Only then they would have accidentally spotted the MC again, without glasses and combed hair.
This would have created all sorts of emotional conflicts. First of all, the MC would have needed to watch the girls be deeply grateful toward the wrong guy, yet getting involved would have, superficially, gone against his dead father's teachings. On the other hand, the girls would already dislike their mother's savior (whom they believed is the savior). So, even when meeting the real savior, who remained silent even when they were showering the wrong person with gratitude, there certainly wouldn't anymore be the kind of reaction we saw here.
But I guess this wouldn't be exactly romcom territory, haha.
