^^^Sole manipulator does not mean jack to Major Airlines-if that's one of the places you wnat to end up. It's about who signed for the aircraft. If you have ever filled out the Airlineapps, they break down PIC time nicley. By the way, what is the CA logging if the Fo is also logging PIC time when they get to fly? They can't both log PIC time.
You have no idea what the interviewers background is. Any flight instructor knows about the part 61 sole manipulator wording. And how is the interviewer going to prove or know who signed for the aircraft?