@Michael Schmidt I think the URL should be valid and public for the upload to be successful. The check indicates the URL is valid but I think the upload failed since the file might not be available in public. You can enable browser developer settings to observe the failure message on the developer console networking tab from the portal.
Here are some troubleshooting steps that could also help.
Since this file is small, I think you can download from one drive and upload as a local file instead.
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and Yes
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