LUO YAN decided to interview the cook first – Mrs. Gilmore. He actually wanted to pick the young butler at first, but then, he changed his mind at the last moment.
He believed that young Gilmore didn't have anything to do with any of the tragedies that had happened in this family. He might be connected to it in some way, but he definitely wasn't the culprit or even the partner of the culprit/s responsible to what happened last night.
The pain and sadness Luo Yan saw in the other's eyes when it was revealed that the corpse was 'William Harcourt' was definitely not fake. Gilmore truly believed that his employer was dead at that moment. Based on his reaction, anyone who saw him at that moment could see that he really cared for William Harcourt.