Vimeo private links don't always work

[afagard]

Describe the bug

Fancybox: 3.5.7

Vimeo private links sometimes renders correct, sometimes says "video does not exist", and sometimes show a completely different video. Reading the issues it seems as though this was or should have been addressed whereas prior to oembed private videos didn't work at all?

To Reproduce

Example code:

<a href="https://vimeo.com/478635699/c9433cf35e" data-src="https://vimeo.com/478635699/c9433cf35e"
   data-fancybox="gallery"
   data-caption="test1"
   class="fancy btn btn-sm btn-clean btn-icon btn-icon-md attachment-action"
   data-toggle="kt-tooltip"
   data-skin="brand"
   data-placement="top"
   title="View"
   data-original-title="View">
    <i class="la la-eye"></i>
</a>

Link that renders: https://vimeo.com/478635699/c9433cf35e
Link that "doesn't exist" but does: https://vimeo.com/478635580/6a63d83df7
Link that returns an entirely different video: https://vimeo.com/478564709/704cadba8e

Desktop (please complete the following information):

• OS: Windows 10
• Browser: Chrome
• Version: 10