Your drawings are correct. If I understand what you have here The float is not shorting it is turning on a power source, +12VDC. That 12VDC is energizing you buzzer. In your parallel drawing, the +12VDC now energizes your buzzer and the relay. The coil resistance of the relay across the buzzer should have no effect.
Unless something else is going here that you’re not explaining, that should work.