Is there any way to fix the "missing camera" iMovie issue? Details below

The missing camera issue occurs when the camera has been turned off, or the SD card removed, before the import has been completed. Have you tried plugging in the camera again to your original library to see if you can get the import to complete? If that doesn't work the only alternative is to begin a whole new import, but the newly imported clips will not contain the edits that you had made to the previous incompletely imported clips.

As I understand your post, you have edited the partially imported clips and they will play with those edits in your iMovie project. If so, you might try playing your project at full screen and making a screen recording of the project preview screen. That would give you an independent movie on your desktop that plays with all of the edits. You then could import that (drag it) into a new iMovie project and complete the project. The new movie would come in as one long clip that you could edit to a limited extent, such as splitting it, deleting split segments, adding titles and effects, and so on. You just wouldn't be able to change or modify the edits that had already been embedded by previous editing.

You can do the screen recording by doing a Command-Shift-5 and, from the controls that appear at the bottom of your screen, select the "record entire screen" option, and then click Record. Stop the recording by clicking on ESC on your keyboard and then clicking on the little black circle with the white square in it at the top of your screen.

-- Rich

I don’t know. You could try plugging in and see what happens.

Sometimes starting over is the most viable solution. Most of us have had to do that at one time or the other. The sceen recording workaround might cut down a lot of the work.

— Rich

Yes. In the Command-Shift-5 control box there is a button called Options. Click on that to get destination options.

— Rich