As we noted earlier, the top result is returned first by the search API call. But, the very first result is some kind of "top result" result, which actually doesn't contain a video ID. And we need the video ID. The second result should have it. (My guess here is that the "top result" thing is just metadata for displaying the top result separately from the rest of the results, since these "API" calls are really only intended to be used by the actual YouTube Music app(s).)