The thing is that the far right in Germany is nowhere near as popular as the Republicans in the US. And the intersection of Tesla buyers and far right voters is very small. Musk made a grave mistake in the marketing department here.
Comparable to endorsing Jill Stein in the US as company for small arms.
He could also refer to the mere possibility of having duplicates which does not mean there are duplicates. And even then it could be by accident. Of course db design could prevent this. But I guess he is inflating the importance of this issue.