I suppose some clear visual cues that the Greeters are malfunctioning would help sell it.

I'm sure a malfunctioning sound and some distortion at the start of the sentence should do the trick.

Ruined forever.

Yep. This is what I was thinking of too. Several elements inspired by Portal might be nice touches.

I'd like to hear them getting stuck on a word like when a game glitches out and makes a repeated sound.

Just another AE remake wish - I want Abe to make the sad noise whenever he's forced to kill a Scrab or Paramite, the same way he does when he accidentally kills a Mudokon.

They're not. It's just translated into English. The same way Lord of the Rings translates the common language into our tongue—ditto with Dune and their imperial language of Galach.

That's just because all gaming and video systems have the babelfish technology already integrated.