Help migrating user profile pictures

Hi, I’m updating my client’s site which is using the User Profile Picture plugin on their current site, and want to migrate all the profile pictures for 1000+ user accounts into the new site which is using the Profile Builder plugin with the User Profile Picture add-on. I can’t find a way to get the profile pictures to migrate across with the user accounts. The profile picture on the user’s profile page is always just the default fallback pic. I’m using the WP All Import plugin for the export/import.

Any help or guidance here would be appreciated. Thanks.