[X] Talk. He seems calm for now, and she doesn't have anything to lose by talking. She's not sure what common ground they could have, but maybe she'll be surprised. She's never really gotten to talk a stronger, older vampire; not that she feels like she needs to or anything.
[x] Lie. He doesn't seem hostile, and maybe she can learn his agenda. He has no reason to know she's working for Buffy, and she could find out if he has some evil plan without him being the wiser. He might even spill something about the secret down here that she's looking for.
[X] Harmony still needs more information. She'll talk to people to try to find out more about Buffy and possibly advice on how to woo her. Stunt to control who Harmony talks to (multiple people may be allowed if circumstances work.)
[x] Kill. Maybe he's older and stronger than her, but she was trained by Buffy, she can still maybe win. He's probably up to no good down here, being a vampire and all, and if she can prove herself now she might still find the secret to Buffy's heart hidden down in this basement.