Running to a portal stone world seems hilarious, so yes, she definitely did seem cartoonish, especially since she could have easily Compelled a number of refugees joining Perrins' army to kill him. The execution of this plan just didn't seem that polished. Even worse is relying on Slayer to do anything - her style has usually been to have multiple fall back strategies to mitigate any failure and build on success, so just sending a goon to do something so important doesn't seem like her.