@Chewy so you think she thought he wasn't so hurt that he was dying?
i get trying to avoid him being seen in that case but you can take your phone and simply not answer it and lie to your spouse, as it's unlikely they will be pinging your phone for location data, i ignore calls or put my phone on silent if i don't feel like talking, i don't leave it at home.
also wouldn't it be easier to keep him home to recover? nosy neighbours cannot see inside the house easily and simply saying G is sick would be enough to explain him not going out that morning to catch the bus.
sorry to raise it but it just doesn't make any sense to me, if she believed she just needed to let G's injuries heal what did taking him out where even a stranger might noticed his wounds and draw attention to them?
she could have stayed home, played good step mum to patch up things with G while reinforcing that he should not tell his dad about this little accident he caused.