If you're looking at the video you Shared from your corrupt video project, it is a done video. You can no relocate the old edit points, since they were part of the video project -- not the Shared video.
Looking to the future you should get in the habit of using the project archiver to backup the project before deleting from your system.
Insanity is hereditary, you get it from your children
I found what I was looking for!
When on the time line, I just need to place the marker, double click the clip and PrE will bring up the preview with in and out points for that clip and the marker placed on the frame where the timeline marker is placed.
One workflow that I use often, is to use Save, Save_As and Save_As_a_Copy, as I edit. I also will have the AutoSaves (extra sets with the latter two versions of Save). This allows me to easily go back, should something horrible happen. I might loose a bit of editing, but seldom more than I can easily recover from. This ARTICLE goes into more detail, and explains the differences between the three common Saves.
Good luck, and glad that you found Trimming in the Source Monitor. Happy editing.