It's not uncommon for matches to be replayed, where it's not gone past half time.
The Dutch FA may not have rules like Afcon's article 82. They might have balanced the second half non-appearance against potential abusive comments, looked at when the match stopped and felt a replay was the best outcome.
That the opponents were from a rough neighbourhood, doesn't mean it didn't happen. Who knows what was said in a brawl?
We know only too well that the most liberal, world saviours, can turn out to be racists. So, being a good guy can only go so far. Perhaps, he didn't hear it, but it happened.
On the other hand, the opponents could have been cynically playing the race card to get away with being a man and a goal down. That's not known for sure.
Play the replay. Don't get goaded. Beat them, and move on.