The only thing that I can think of here is that the video example is getting the image from the current post and when you’re using a section template you are trying to get the image from a different post than where the image is shown. It may be a case where Elementor is using the wrong post ID, and I don’t know anything about elementor so I can’t tell you how to fix this.
You should contact elementor support to ask this question and see if they can help you sort it out.
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