Well as a on-set nickname it's fine. Like Celtic mentioned the on-set nickname for the Predalien was "Chet". Again, on-set that's fine.
The difference is, when the merchandise was released that creature was called "The Predalien". It wasn't called "Chet".
But for some reason (at least for Sideshow) the first piece they're releasing IS labeled "Mr. Black" which uses the on-set nickname.
That's the problem.
This has to do with merchandise and absolutely nothing to do with the movie. Like I said earlier, this discussion spilled over from another thread. It really has no impact on the film. I don't recall ANY Predator/Alien movie where the creatures designated names (Official or on-set nicknames) were used in the film. For example, ALL the Lost Hunter's (even including that name of "Lost Hunter's") were fan based nicknames.