Thank you for reaching out! Just an FYI I removed your backup attachment since this is a public forum I didn’t want your site hanging around for others to download.
I took a look at the file you provided but it was empty. So it’s possible that Updraft had trouble creating the backup in the first place and that’s why it didn’t import.
You could try creating a full site export with the plugin WP Migrate Lite (it’s free) and then using that file to import.
If that gets the same or similar type error, you can unzip the file and try to manually import it with these steps: