I apologize profusely.
I had tested this out before, but hadn't realized that I had left the original project folder in place, even though I had created a new copy of that project on a different drive.
So, opening the project from the new location, the video still played fine, but in actuality had been pointing back to the original location, despite the video coming along to the new location.
When I went back to double check everything, and realized I had left the original project folder intact, I deleted the original project folder, went back to open the project from the new location, and indeed the audio plays, but the video is toast.
I had a flawed situation in place when I made my earlier suggestion that this would work.
I withdraw that earlier suggestion, and will strive to do better at setting up testing of concepts prior to recommending them, in the future.
I do NOT like the hard-coded internal location information method of pointing at imported video. I think it should either give you a way to modify the location of the video for the project somewhere, or offer to save a local copy of the video in a Video sub-folder of the project folder (like with audio clips), or in some other way enable some way of telling it that the video has moved. BAKERS?????
Perhaps they could create a new entry in Preferences, at the Project level, for a path to video for the project, and during project open, check to see if the new path field had been populated already, and if not - take the hard-coded path it had been using before and populate the new path field with that location, as a starting point. If then the video is not found, a 'locate video' dialog could supply the means of entering a new location for the video, and the new location used to populate the Video Path field in Project-level Preferences.
Bob Bone