I really hope it’s not the case because I’m not a fan of NTR, but there’s something to note here.
She asked him to be his manager for the day, but she did not describe how she was dressed.
When he got to the place and heard the noises, the images shown were from someone dressed exactly like her and her CEO and since our guy didn’t know how they were dressed, there’s no way he could imagine the clothes they were wearing.
But again, let’s hope it’s nothing major, because she’d be a bitch for doing that after saying she likes him so much and have fallen for him completely.