Oh Cowl, yet another plot thread that has gone missing from the fabric of this series... 
Or has he? If Nameless is Cowl then is is aware that Mab suspects him of involvement in Arctis Tor at the very least, so he has been keeping a low profile, he would rather use an intermediary not part of Winter, preferably a mortal to advance his Agenda.
I rather think Listen has been working with Nameless, or at least under his instruction. It’s how Listen knew to attack The Carpenters, he still has contacts within Winter and would know about the protection detail, and maybe even Maggie. Hell Mab might have leaked him the info to find out whether he was tied to the Fomor, or not. It’s her style, then tipped off Molly. Ethnui and the Fomor would dismiss Harry as insignificant. Cowl on the other hand has had plans ruined by Harry before, so would not dismiss him as insignificant and put in a contingency plan led by his handpicked wet works man to prevent him doing it again.
If that is the case then Nameless/Cowl has been active in Dresden’s life from just before Bombshells right through to Battle Ground through Listen, where we weren’t aware of it. During this period he was working for Marcone, when Marcone was putting up significant opposition to the Fomor. If locked out from Winter, Marcone makes the next best target.
