Ilshana goes over to the giant and finds a spot where she can see his eyes. Her voice sounds sympathetic as she speaks.
"This doesn't have to end badly for you," she says. Her eyes fluoresce eerily, shining bright lurid green as her voice takes on a strange resonance that sends her voice to the hindbrain, compelling obedience. "Just answer our questions."
(Last 2nd level spell slot on Suggestion. DC 15 Wis save. Can't hurt to give it a shot.)