If you’ve lost your sound and images, but had obtained them from a shared deck, if the shared deck is still available you can import it into a new profile, and then copy the sounds and images from it into your original collection to restore the data.
For more info: Manually Adding Media
alternately you can use https://ankiweb.net/shared/info/1102281552 (great for updating decks too)
Even if you downgrade i don’t think it would resolve the issue
Sound/image media files have gone missing! - Frequently Asked Questions
WARNING: This is an unofficial duplicate upload of Image Occlusion Enhanced (https://ankiweb.net/shared/info/1374772155). Please be wary of listings like this as they are not under the control of the original author and could be updated with malicious code in the future. Just like the warning above says: “As add-ons are programs downloaded from the internet, they are potentially malicious. You should only download add-ons you trust.”
You might need to remake some cards, use only the official image occlusion add-on
might not work but try this: Some of my IO cards are empty
As last solution, try to continue your post here Image Occlusion Enhanced [Official Support Thread]