It is a logic puzzle, so 'lie' means saying the exact opposite of the truth.

The clues they give are below, from the walkthrough. You can mindread Keara or find a note (near the first statue IIRC) to learn that they lie.

Quote
-There's one statue near the entrance (1), two statues in the room to the northwest - one in the northwest corner (2), and one in the northeast corner (3) - and two statues in the room to the southwest - one on the south wall (4) and one on the west wall (5).

-Statue 1's hints: Mayhem is not in the same room as Havoc. Devastation is in the same room as Chaos.

-Statue 2's hints: I am either Devastation or Chaos. Waste is in the same room as Mayhem.

-Statue 3's hints: Mayhem is alone in his room. Havoc is in this room.

-Statue 4's hints: I am neither Chaos, nor Havoc. Chaos is neither in my room, nor in Waste's.

-Statue 5's hints: I am in the same room as Waste. I am neither Mayhem, nor Waste.


Once you know they lie, just write down the clues opposite of what they say. My interpretations of the clues looked like the following:

Quote
M with H. D not with C

2 not D or C. W not with M

M not alone. H not in room with statue 3

4 either C or H. C either in room with statue 4 or W

5 not with W. 5 either M or W.


These are enough clues to figure out the names:

From the last clue, statue 5 must be M.
From the first clue (M with H), statue 4 must be H.
From the second clue (2 not D or C), statue 2 must be W, since that is the only option left.
From the forth clue (C either in room with statue 4 or W), statue 3 must be C
this leaves statue 1 as D

The solution is:
The statue at the start is Devastation. In the fire room, the statue on the west wall is Mayhem, while the one on the south is Havoc. In the green room, the western statue is Waste, while the eastern one is Chaos.