Closed Captioning without Audio

Hi, Wendy.

You can add captions to either video or audio on the timeline. If you insert a video, it doesn't need to have audio to let you add captions. Similarly, if you add a silent audio file, it will still allow you to add the captions.

Here's a quick workaround:

• Click on Insert -> Audio. You can choose Text-to-Speech and type or copy/paste your text.
• Make sure Generate Closed Captions is checked.

• On the timeline, right-click the audio track and choose Edit Audio. 
• Select the entire sound wave, then click Silence.

Let me know if this works!