How to recover lost Photos on MacBook Pro?

My wife was keeping some photos in this folder (evidently it was sitting on her Desktop) rather than moving them into another folder for some reason.

We bought her a new MacBook Pro and she updated the macOS on her old one for data transfer to the new one. Evidently this wiped or moved the photos in the existing Recovered Files Folder on the old MacBook Pro because it is empty now.

Does anyone know what happened? Are those photos gone? Alas, they were not named so I have no way of looking for them by name with search software, but I suppose that I could look by type if they are possibly on the drive.

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