This episode points to both the potential and the risks of drawing open-source intelligence from videos. Clips such as these can give clues to political and military developments, but those clues can be diversionary or misleading --- if the aim is to provide "truth", rather than spin or wishful thinking --- without contexts.
Contexts in this case would include the relationship between Hezbollah and Iran as well as between the Lebanese organisation and Damascus, the state of the conflict in Damascus Province, and the interests of the insurgents who have put out the video.
And there are wider contexts beyond this. The supply of arms by Iran and Hezbollah to Syrian forces is not one-sided. It takes place in a larger arena in which the "West", Turkey, and Arab States provide their own weaponry to the insurgency.
None of this is to deny the need to assess this video. It is an argument to assess it properly.