Pretty sure he's only allowed to pick guys from Quickstep, so Van Aert, Hermans, Stuyven, Van Hooydonck and Dewulf would probably decline. That leaves Serry and Lampaert. Even if he would pick them, he still has 3 open slots. But i'd think he'd rather pay his gratitude to the guys who helped him in the Vuelta than the Worlds anyway.
As i said before, i think he'll take Van Wilder, Serry and Vervaeke. Then Hirt (unless that's one of the 2 guys management pushes) and Masnada. Personally i'd take Cattaneo over Vervaeke, but given Vervaeke's been a loyal dom all year, i think he'll pick him.