You won’t be surprised to hear I disagree with you. If Riss was excluded, he’d have been equally unhappy, as would many others. But that’s not my point - all these kind of incidents are subjective judgement calls (so people will disagree), but the problem is that the referees aren’t allowed to have an opinion of “neither to blame/both to blame equally”. So even if they think that, they have to exclude somebody. A very strange and misguided rule imo.