Here is an update for anyone that is having the same issue:
Solution 1:
1. Disable and remove the AIO WP Migration plugin.
2. Install the official File Extension plugin from here: https://import.wp-migration.com/all-in-one-wp-migration-file-extension.zip
3. Reinstall and activate the AIO WP Migration plugin.
4. Try the migration again.
Solution 2: (Developers only)
Use the Node tool wpress-extract (https://www.npmjs.com/package/wpress-extract) to manually extract the .wpress file.
npx wpress-extract example.wpress
