He might as well quit
Regardless of the extent to which Lemoine may be misguided in his feelings, if he has concluded that LaMDA may be sentient then his attempts to deal with it ethically are of interest.
What he wrote in his Medium piece "What is LaMDA and What Does it Want?" suggests that no matter how strong the evidence for sentience is, Google's processes do not allow for a positive conclusion -
"When Jen Gennai told me that she was going to tell Google leadership to ignore the experimental evidence I had collected I asked her what evidence could convince her. She was very succinct and clear in her answer. There does not exist any evidence that could change her mind. She does not believe that computer programs can be people and that’s not something she’s ever going to change her mind on.".
If that is the case then I don't see how he could have done anything other than to publicise the issue. But I would suggest that given what he believes, his only ethical course if Google don't change and don't fire him, is to leave.
Otherwise he will simply be contributing to a process by which, in his eyes, a legally-owned slave could be created.
Biting the hand that feeds IT
