After restoring my iphone from a backup, my Whatsapp videos are no longer available in their chats

After the iOS 16 update I had some phone problems that warranted doing a factory reset. Just prior to that I did a phone back-up to the icloud and then proceeded with the reset and restore from the back-up.

Following this I noticed that while everything else had been restored, my Whatsapp app was stalled in the restoration. After about an hour of it not moving at all, I decided to delete the app and reinstall it. That worked quickly, but all of my Whatsapp chats from that moment to about 4 days prior to that were totally gone. The messages before that were all there. This has me assuming that the iPhone did the backup from something other that the iCloud back up but rather a Whatsapp backup?

Also, and this is the greatest problem, I noticed that while all of the pictures in the chats are still there, not of the videos can be played but rather are just a blurry image. Any ideas what I can now do to remedy this?

A similar thing happened to the iMessages, where the photos are in the chats if I scroll up, but they are not to be found if I look in the album for that chat (only several photos are there).