Inspecting all foster families just because of this incident seems like a knee-jerk reaction. However, I do support foster families being inspected in general to ensure that the children are well-cared for, the foster parents are doing well and need any support, and to ensure other standards of safety and well-being.
I imagine foster parents have to go through a lot of hoops to have a foster home and make sure they are psychologically sound. We've heard enough stories of abuse and neglect in foster homes that could be prevented. Then again, we hear about those stories of abuse and neglect in regular homes, as well. It's just that foster homes are inspected and monitored and can prevent abuse/neglect, whereas regular homes aren't.