Pinning only affects your personal view. Select “speaker with shared screen” for recording, and Spotlight the Speaker – when other people speak, their video won’t appear, only the spotlighted participant, which could be the host, or anything you choose.
One of the interesting things about Zoom is that the client app behaves differently with only 2 people in the room. I don’t recall seeing any definitive documentation on the differences, but there are some. I don’t think you can Spotlight with only 2 participants. You might have to join with another account to get what you’re looking for.