It's short, but what's there is well done. The animation is very smooth and is certainly the stand-out aspect of the film, especially for a THAC film.
You did a good job with the verbal communication, bringing back memories of the early Lego games and their limited vocals. (Also, the ENDing screen is ironic.)
The major issues here would simply be those present in most THAC films. The quick runtime cut short the "show, don't tell" rule, leading the alien to simply look slightly more curious with the teleporter, rather than completely bored with his current job. While he let out a big sigh, there wasn't enough context to know if that was because there was so much trash, or the job itself had him down. A similar problem is present on the back-end. It ended suddenly on a title screen, rather than a quick montage of shots would have given it a better sense of their growing friendship.
While expansion certainly would have aided the film, what's here is well executed and fun. Even as-is, this stands out as very well polished, especially so for a THAC film.