This is because the settings are not set up correctly in the Video Category itself.

Navigate to:
  1. onMessage
  2. Content
  3. Videos
  4. Select the Category your working with
  5. Settings
  6. Ensure these 2 Video Information checkboxes are selected: Allow titles on videos and Allow descriptions on videos
User-added image

The only way the Video File name will display and not create a generic numbered video file name is to have these items selected.

Note: Keep in mind if you change these settings they do not change what was already uploaded just anything new going forward in that specific Video Category.