Tristan didn't know whether to laugh or cry when he heard the last remarks of his grandfather. He was also overwhelmed and stupefied after knowing that his grandpa already mobilized police reinforcement and military reinforcement just to find his wife.
He couldn't blame them if they mistook her as a missing person. They thought Zhen-Zhen was in school and it's already nighttime in the City of Empire right now. Zhen-Zhen should be at home by this time but she hasn't returned yet.
She teleported from her school going to Tristan's place so Zhen-Zhen didn't inform anyone about her whereabouts. It was natural for his grandfather and parents to worry about his wife.
Zhen-Zhen was staying at the Davis Mansion after she stayed at Meyer's residence for a few days. Of course, they would wonder where she went if she didn't even go home to her parents.