He didn't report it to police immediately due to his own confusion of dates, only discovering three months later (when reviewing his work records) that he'd spotted the young person the same night Murray disappeared.
由于自己搞不清楚日期，他没有立即向警方报告，而是在三个月后（在审查他的工作记录时）才得知他在穆雷失踪的那天晚上发现了这个年轻人。