Envato Elements nearly all Previews broken in Elementor Blocks

In the Envato Elements plugin (v1.1.19 and earlier) preview images are currently broken and missing from the source server for nearly all Elementor Blocks. Elementor Blocks are not useful without being able to see previews of what is being installed. It appears that the preview images were taken down from, or relocated on, the source server.

This is happening on multiple versions of the Envato Elements plugin including the latest 1.1.19 release.
It is also happening on multiple browsers.

This can be reproduced by going to this default wp-admin path:
/wp-admin/admin.php?page=envato-elements#/elementor-blocks

or via the WordPress UI: click through Elements / Template Kits / Elementor / Blocks

Here are some sample broken image links from the Header blocks section (I know the source server seems odd but it’s consistent for all previews):

https://bob2cnnvzm-flywheel.netdna-ssl.com/wp-content/uploads/sites/70/2018/08/screenshot-4-1544564044.png

https://bob2cnnvzm-flywheel.netdna-ssl.com/wp-content/uploads/sites/137/2018/11/screenshot-5-1544565831.png

https://bob2cnnvzm-flywheel.netdna-ssl.com/wp-content/uploads/sites/105/2018/09/screenshot-5-1544567461.png

For comparison, here are some working image links from the Pop-Ups blocks section which is the only Block type with currently working previews

https://bob2cnnvzm-flywheel.netdna-ssl.com/wp-content/uploads/sites/137/2019/01/screenshot-838-1548065220.png

https://bob2cnnvzm-flywheel.netdna-ssl.com/wp-content/uploads/sites/33/2019/01/screenshot-1036-1548064062.png

Any help here would be most appreciated. We went all-in on this Envato Elements solution for our site build and are unable to proceed!

Thanks in advance!

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