Lucas had been following exactly what Sara had done on all the days she had gone missing while in KEI. That was the only wise thing he could do. The information he had obtained from Coraline proved to be useless. It was important - definitely, but it was useless because neither of them could figure out how to use it.
Hence, his decision to mirror Sara's movement during her disappearances. If she had left Bonington Hall at five fifteen in the morning, he left Bonington Hall at five fifteen in the morning. When she walked at the Northside garden around six-ten in the evening, he walked at the same spot at that time.
Every path she took, he followed. Every deliberate action, he copied. Yet, nothing happened.
He was not sure what he was supposed to look for nor did he know what to expect. The only thing he knew for sure was to check the time-lapse, which did not seem to show any difference at all.