Well, they had to knock the kid out quickly, and they didn't want to kill him, so that's really the best way.  And Brent is a typical dumb idiot type of guy, so he's meant to sound like that.  Jack and Brent are "friends" in an acquaintance type way, Dan hired them to help kidnap his daughter and not for much else.  There are two other people besides them in on the operation whom you'll meet later. 

And Dan might very well want some money out of the other parents, or hold them hostage for a different reason.  He will certainly be contacting Alaina to gloat over his success at getting Lexy, he's just that kind of bastard.  And it would be too easy for Severus to just cast a spell, so I won't be going that route, you'll find out why.  And while they might decide to involve the real police late ron, that'll only be after they've trounced the bad guys to within an inch of their lives, and heven help them if Tobias goes on the rescue attempt, they just might end  up in a cemetery, because nobody messes with his grandson.  And if I do decide to kill off Dan, they could always say it was self defense, or they could simply vanish the body, since Dan is there illegally, and if he disappears, oh well.