Yhea, like hell Prez isn't trying to get Shiina jumping the gun by putting Komachi near her almost all time long. He know that Shiina would continue going on Komachi.
His logic toward Shiina show that there is almost no turning back for him, "she is not reedemable so she need to be killed for the sake of (justice or shit like that)"
As for the ending of the chapter, i'm supossing it's Akira's dad. Question is how did he track down Akira ? Did he really put a GPS on Akira's phone himself ? Or did someone help him ? And in this case, why ? Not gonna lie, i'm fearing that Akira gonna die.