"imovie incompatible media" and file dates

The most recent version of iMovie in Mojave can scan your library and update any movies that will be incompatible with the next full 64 bit version coming this Fall. It does this by converting your old originals to a more up-to-date file type and then copies your originals to a folder call "iMovie Incompatible Media." Here is the problem: When I look at an original file that was moved to the "incompatible" folder using Finder, the creation date is the original date of the filming (e.g., one of my clips has the creation date Apr. 24, 2007 which is accurate). Using "Reveal in Finder," the new converted file inside iMovie has the creation date reflecting the moment the conversion was made (e.g., my 2007 converted file shows a Creation Date of today (Aug. 18, 2019)). I understand that Finder simply shows the actual date of a file's creation, and since the original file has been converted, and not merely duplicated, then it will have a new creation date, so nothing surprising here. However when I click on the Info button above the clip in iMovie (upper right) it shows the date Nov. 5, 2017!! This is also the "original" date that shows when I click on "Adjust Clip Date & Time" function. Ironically, when I sort all the clips "by date" in the menu pane to the left, this clip is correctly sorted under the year 2007.

So my new converted clip is providing three dates: 1) the original 2007 filming date when sorted in the left panel, 2) the Nov. 2017 date in Info. and Adjust Clip Date & Time function, and 3) today's file creation date in Finder. Can someone help me understand where in the meta-data iMovie is grabbing the Nov. 2017 date (I assume it was from some past action) and why it isn't grabbing the actual filming date as the original file shows and iMovie senses when sorting. Also is there an easy way to batch convert all my videos (they all have similar problems) to reflect the original filming date in both the Info. pane and Adjust Date and Time function?

Thanks!

John