Photo file names and date/time stamp are not synchronized on iPhone 13 Pro

I load the photos via iCloud onto my PC. The photos are then run through an App to change the name to the date and time using the EXIF data. Attached is a screenshot of the filenames and date/time stamp before any processing other than the downloading of the photos via iCloud. I sorted by date so it would be easier to see the problem. Note the file names are not in sequence.

It's been a week with no communications. Is someone working the problem? Here's what I discovered.

On my phone, I looked at the timestamp for each photo.

IMG_0352.HEIC May 11,2022 12:53

IMG_0353.HEIC May 11,2022 12:54

IMG_0354.HEIC May 11,2022 12:54

IMG_O354.HEIC May 11,2022 12:54

IMG_0355.HEIC May 11,2022 12:54

IMG_0356.HEIC May 11,2022 12:55

There were only 5 photos, and one of them was out of sync AFTER loading it to the PC via iCloud Photos.

After downloading it via iCloud Photos,the last photo is in second place rather than last. This same photo's timestamp is out of sync in Google Photos, also. What gives and is anyone working this problem?