“I am no expert on Australian wildlife, but I have not heard of dingoes drowning humans.”
They didn’t drown her. They bit her to death. Third fatal attack in that area.
The autopsy showed that she died by drowning, with the dingo bites being post-mortem. At most, the dingoes might have forced her into the water. Yet she would have the advantage over such land predators in just a couple of feet of water so as to be invulnerable to attack if they went into the water after her.