[Galaxy S III Original Android Development] curiousrom:
Missing Contacts Backup & Sync - Google Camera

"...contacts.google.com and he says he can only see email addresses for both of google accounts" - So that means that the contacts where not set to his Google accounts in the Contacts app so it does not matter if sync was enabled or not.

"I feel bad I haven't manually made a backup of his contacts before wiping data" - Yep, you should feel bad. ;) Most people I help with fixing their phone's OS and/or setup have it set to save contacts to phone & importing to their Google accounts it's the first thing to do. Or using a third-party app to backup which I did not do in a long while as I download a copy of my Google Contacts data to PC once in a while for double safety ( https://contacts.google.com/ > More > Export).

"..he was using Microsoft Outlook" - So log in to https://outlook.live.com/people/ and if his contacts are there you can export them to CSV or go to https://contacts.google.com/ More > Import directly from a outlook.com account or from the CSV export.

Then Lineage > Contacts > 3-dots > Manage accounts, > Settings > Default account > select a Google or Outlook account which I never tried in LOS so please report back if it works or not. And 3-dots > Import/export > Import from SIM card in case some where saved there. You can always merge/delete duplicates in https://contacts.google.com/

"I did copy/paste content of /sdcard before wiping data so is there a way to retrieve contacts from there?..." - Normally if save to phone is chosen the contacts are saved to a .db in /data/data/ and not to /data/media/0/ which is the real location of the folder that the /sdcard sym link is pointing to. More details here. But you could always search that sdcard backup with: *contacts*.

If he had a Microsoft Outlook app installed & not linked to his account maybe it stored some data in sdcard?

If all the above fails maybe he has a full Nandroid backup or a Kies backup or a Samsung account w/ a backup from which contacts may be extracted. Search: retrieving contacts from kies backup and How can I retrieve contacts from Samsung account?

Any ideas if openGapps PICO syncs phone contacts? - Check the Open Gapps Package Comparison and you will see that only the way too big for the S3's specs Stock & Super packages include the Google Contacts app. The stock LineageOS Contacts app (com.android.contacts) works fine for syncing to my Google account.

Obviously you can always download Google Contacts from the Store even if you installed the smaller Open Gapps Pico.

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Google Camera Crashing

Always mention your LineageOS version because "latest build" will not mean anything in a couple of days. ;) You also did not mention your Google Camera's version.

As I explained in the Default Video Player, Open Camera & Google Camera post the most recent version that can be used on S3 Lineage 14.1 is the older Google Camera 2.7.008 in apkmirror as this legacy version is not available in Play Store.

While I use the stock LineageOS Camera most of the time & Open Camera for fancy advanced camera settings I have also installed Google Camera 2.7.008 on stock Official Lineage 14.1 updated to 2018-07-19 on my S3 i9300 + Open Gapps ARM Pico + Lineage ARM super user add-on and just tested making some photos w/ & w/o flash, changing some settings (resolution, manual), shot a video & made a panorama w/o any problems.

Edit: Did you try Settings > Apps > Camera (the Google one has a rectangular gray camera icon) > Storage > Clear Data & hard reboot?

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