Yeah, I looked it up and the reason Lara sounds different is because its a different VA being used for her in DBD versus the 2013 game that the base model is from. That and the original VA was Camilla Luddington and the VA used for DBD is Hayley Atwell aka Peggy Carter from Captain America: The First Avenger.
Laura probably wouldn't be scared of the legion since they're dumb kids, except maybe Frank since he's the actually crazy one of the bunch. Now the monster killers she'll be scared of.