Losing custom field content in lecture notes due to syncing from another PC

Hi there, I recently lost all my anking custom lecture notes field content because I synced from another computer and it says that I need to do a sync from Ankihub. Didn’t notice that removed everything from that field until a week later. The lecture note field was always in the protected fields but it still happened. I know I still have them in my backups. The data is still on my iPad as well. I know I can do an upload from my iPad but that will remove my one week’s progress. Is there any way that I salvage the lecture notes without losing all my progress this week? Thank you. Any help is much appreciated.

I believe the only way is restoring from a backup. Does anyone else have any other ideas?