If I read your question correctly, there are several ways to do what you are asking for.
One would be to drag Video Clip, with its Audio to the Timeline. Initially, that will give you both the Video & Audio from that Clip. Then, if you wish a different Video, you could drag that Video Clip (Audio & Video) to Video Track #2. That will visually replace the Video from Video Clip #1 (on Audio and Video Tracks #1). Then, Alt+click on the Audio Stream of Video Clip #2, and Delete it. You will then have the Video from Clip #2 showing (as an overlay, it visually replaces the Video on Video Track #1, but will now have the Audio from Clip #1 playing.
Again, there are other workflows, to get the same results. If the above is what you want, but you wish to explore some of the other workflows, let us know, and someone will walk you through those processes.
Good luck, and let us know if this gets your desired results, please.
As this is basically the same question, as posed in another thread, I have made a Copy of my Reply here, and added it to the other one.
I will Lock this thread, and think that we can continue in one of the other two (similar, but different enough, that it is possibly good to continue in those).
If you do not feel that this is productive, just send me a Private Message, but let's work in the other two threads for now.