This is the same exact video that was originally uploaded to Jadusable's YouTube channel. The title is the same, though the description and tags are new. The description is the final conversation between Hank and Ben before the latter drowned. This is the first mention of Diana as well.
Details as of 9/9/18.
The phrase "No one came." fades in as we hear underwater ambiance. Near the end of the video we hear what sounds like someone beginning to run out of breath.