I have a suggestion that may explain the “sandwich”.
Try unlinking the clip on track 2 you dragged left with the main track.
Not sure how to ‘unlink’ the clip. Is track 2 the bottom clip?
The tracks number from the main track, the bottom one, upwards. You can use the “link” icon at the bottom of the editor to link/unlink specific clips or use the link icon alongside the track to link/unlink the whole track.
I can see from you latest video you have a lot of clips in your project.
I think your problem “lumasandwich” stems from how your clips are linked.
I’m not overly familiar with the linking feature but have tested on a simple project and it looks like it can be quite a complex area, as the topmost track can be linked to the track underneath it and so on down to the main track (the one that has the insert/overwrite arrow next to it).
Hope this help you sort things out, let us know how you get on.
Good luck - keep safe.