Point 1: Premiere Pro does not overwrite/cut original material in the timeline. The actions are only cutting a proxy version, leaving the original materil in the project panel unaffected.
Point 2. Regarding the clip in the timeline that has been left with a gap in it that you wish to join...
...delete the right hand clip and, with the mouse, drag the tail of the left hand clip to the right. It will expand out to the original length. You can also delete the left hand clip and drag the head of the right hand clip to the left :^)
(I have to place them on Video 1 if I want to use video transitions, right? I'd rather place the short clips onto Video 2 so the Original video would stay underneath)
If you'd rather put it on video track 2, go ahead, when you add a transition to- or from video2 (on the beginning or end of the desired clip on V2) it will transition to/from video 1.
What can I do to delete the short clip, and bring back the Original overwritten video so that it plays seamlessly with no gap and no jump just as it did before the overwrite?
exactly what Jon said.
Thank you Jon and Felix for your replies. I'm back in business!
I had watched a video tutorial that said to use video transitions, both clips needed to be on the same video track and like a zombie idiot I just followed directions and didn't even try transitioning between video on two different tracks. Now I have, I see that it works, and I am proceeding with all overwrites on their own video track. Thanks for that, Felix!
you're very welcome!