Hi jeterway,
The article Edit photos and videos on iPhone specifies "After you take a photo or video, use the tools in the Photos app to edit it on your iPhone."(emphasis added) The ability to make changes or edits to photos may be restricted to those captured with the device rather than ones synced in from other sources.
You can also try the steps in View photos and videos in the Photos app on iPhone to view the meta data associated with the images in question if available:
"See photo and video information
To see saved metadata information about a photo or video, open it, then tap
or swipe up. Depending on the photo or video, you see the following details:
- People identified in the photo
- A caption field to describe the photo or video, and make it easier to find in Search
- Items detected by Visual Look Up
- Whether the photo was shared with you in Messages, another app, or iCloud Shared Photo Library
- The date and time the photo or video was taken; tap Adjust to edit the date and time
- Camera metadata such as lens, shutter speed, file size, and more
- Where the photo or video was taken; tap the link to view the location in Maps; tap Adjust to edit the location"
Regards.