We had a similar use case at my company, although the amount of actual video was very low. One thing you should consider is permissions. If you need permissions at all then a wiki is not for you, wiki's are not designed with fine grained viewing/editing permissions.
We've had a great success with an internal Drupal CMS instead. Web developer to put the company style on it and put the first few articles in, quick training session on Drupal for managers to cascade down to their departments.