IME A child who bites another in the face is a known business liability.
Red flag/Deal breaker.
Bites to the face are probably the most common cause of State complaints and lawsuits filed. The pain, infection risk and scarring are simply not worth waiting it out to the victims family. They won't care about the biters development, only your direct supervision and prevention of injury.
The only feasible plan I know is direct physical supervision, preventing escalation before the bite, separating the biter from other children entirely or termination.