Apparently the question of whether or not there was a gun will remain unless or until the cops release sufficient video footage to establish one way or the other.

Cops merely shouting 'drop the gun!' means nothing in such cases, as they always do that when they've decided to shoot someone, regardless of whether or not their intended victim is armed.

And then there's this: I worked for eight years in a 92-bed county-run psychiatric facility.  Many, perhaps most, of the people brought there for evaluation were brought by the cops.  The rule was the cops couldn't bring their firearms into the intake building.  So I had opportunity to repeatedly observe them while they disarmed outside at their patrol cars (without them seeing me).

I last things they always placed in the trunk were their 'throw-downs'--the once-fired, unregistered handguns they strapped to their calves, beneath their trouser legs, to make sure that whoever they shot 'had a gun'--regardless of whether they did or not.