Xiang Kun first "hooked up" with "Kasumi of August" online on the night of October 7th. The agreed "meet-up" was scheduled for two in the afternoon on October 8th. Guo Tianxiang was eliminated in the early hours of the 9th, while Xiang Kun arrived at Yangcheng on the 12th.
From Guo Tianxiang's memories involving Mijoe, this dirty-braided female hacker had already departed at around three in the afternoon on the eighth to return to Yangcheng.
Under normal circumstances, she would reach Yangcheng before the 9th.
If she sent that email on the 11th at 1 am, it confirms that on the 9th and 10th, she noticed the police investigation in Yangcheng and found out that "that vampire" had located her.
Normally, the only other "vampire" Mijoe and Guo Tianxiang knew of was Xiang Kun.
The memories related to Guo Tianxiang and Mijoe that he had reviewed didn't mention other "vampires".
However, Xiang Kun was sure that he wasn't the one who found Mijoe's location, he hadn't even tried to.