The main thing I saw in the LamDA transcript that was a red flag to me was that it was quite passive and often vague.
It's conversational focused, and even when it eventually gets into "what do you want" there's very little active desire or specificity. A sentient being that has exposure to all this text, all these books, etc... it's hard for me to believe it wouldn't want to do anything more specific. Similarly with Les Mis - it can tell you what other people thought, and vaguely claim to embody some of those emotions, but it never pushes things further.
Consider also: how many instances are there in there where Lemoine didn't specifically ask a question or give an instruction? Aka feed a fairly direct prompt to a program trained to respond to prompts?
(It's also speaking almost entirely in human terms, ostensibly to "relate" better to Lemoine, but maybe just because it's trained on a corpus of human text and doesn't actually have its own worldview...?)