First identify which date is wrong
A media file can have a filesystem creation time, filesystem modification time, embedded capture time, digitized time, timezone offset and application database date. They are not interchangeable. ZIP extraction commonly assigns a new filesystem creation time even when the camera capture date remains embedded.
Open several affected files in a metadata inspector and in the destination application. If EXIF DateTimeOriginal is correct but Finder or Explorer shows the extraction date, the problem may be the displayed filesystem column rather than lost capture metadata.
What Google keeps in supplemental JSON
Google states that original photo or video metadata remains embedded when it existed, while additional information managed in Google Photos can be exported in a secondary JSON file. This may include an edited timestamp, description or location that is not present in the original camera file.
Do not delete JSON sidecars because a camera image already looks healthy. Screenshots, scans, messaging-app images and dates edited inside Google Photos are common cases where the sidecar provides the most useful timeline evidence.
Use every ZIP and preserve filenames
Large exports are split into numbered archives, and related evidence may not be in the same part. Process every part as one library and keep the original archive names until matching and integrity checks are complete.
Supplemental filenames can be shortened, use several suffixes or sit beside repeated album copies. Reliable matching prefers local exact evidence and JSON titles, then applies stricter rules to cross-folder candidates.
Preserve the instant and its timezone
A Unix timestamp represents an absolute instant. EXIF display fields usually represent local wall time and need an offset to remain unambiguous. Writing the UTC clock value directly into a local-time field can shift a trip by several hours even though the source timestamp was technically valid.
When reliable GPS is available, a repair can determine the location-aware offset for that instant. Without reliable location or offset evidence, the safer result may be a reported limitation rather than a guessed timezone.
Write format-appropriate fields
JPEG and HEIC photos, PNG images and video containers do not share one universal date field. Video timelines often depend on QuickTime creation fields in addition to filesystem time, while photo applications commonly prioritize embedded capture time.
A bulk command that writes the same tag to every extension can appear successful yet remain invisible in the destination. Use a format-aware repair and verify the fields the target application actually reads.
Verify a representative sample
Repair to a separate output, then inspect files from different years, devices, timezones and formats. Include screenshots, edited dates, HEIC files, videos and at least one file without a matching sidecar.
Compare the repair report with what Apple Photos, Synology Photos, Immich or another destination displays. Keep the Takeout ZIPs until the complete output has been checked and backed up.