That is actually the problem. I don't want to switch audio, I want both tracks. I drop the multi-cam clip in with the in-helmet mic audio track picked, then drop the audio track for the engine noise in the timeline on a second audio track. Then I select all three tracks, and link them. Then when I go through and make my cuts, it cuts all three tracks so the audio stays in sync between my talking, and the engine noise.
Once the cutting process is done, to switch views I do the multi-cam edit with camera angle switching only, so I don't touch the audio when I do those switches.
Like you see in this picture, I end up with one video track that is multi angle, and 2 audio tracks.
View attachment 5521