Videos using amp-video-docking don't show docking controls when used with amp-next-page

### Description

AMP videos, when used with amp-next-page, don't show docking controls or docking overlays. However, if a video is present before the amp-next-page setup, the subsequent videos in the list work fine.

### Reproduction Steps

Here's a Glitch example made using an existing amp-next-page example: https://obsidian-evergreen-november.glitch.me
Code: https://glitch.com/edit/#!/obsidian-evergreen-november

Add the video component to either views/article1.html or views/article2.html. Docking works, however, docking overlay doesn't show up.

If you add the same video to views/layouts/index.html, the docking overlays in article1.html/article2.html work fine.

### Relevant Logs

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### Browser(s) Affected

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### OS(s) Affected

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### Device(s) Affected

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### AMP Version Affected

_No response_