Does The New MEN IN BLACK III Trailer Have Unfinished Green Screen?

A new MIBIII trailer shows off more of Brolin's Tommy Lee Jones imitation... and an unfinished bit of green screen?

So check out this screengrab from the above trailer:

Is that unfinished green screen in the tank behind Will Smith? Will the final movie have aliens swimming in that tank? If so, how crazy is it to have this shot in the trailer? Of course, maybe the film just features a big tank of alien green goo and there will never be an effect in there.

But what does it say about the tortured history of Men in Black III that I am entertaining the idea that an unfinished FX shot made it into the theatrical trailer? Also, how bad does this movie look? Why am I asking so many questions in this post?