With just 1 pin high and 1 pin low, there is no way to have multiple LEDs turn on.
Your testing looks to me like you have the part at the lower right of the datasheet,
where you applied a High (resistor & red wire) to a common anode pin and then walked a low (white wire) across the discrete cathode.
There must be some weak connections between the cathode pins to make them light up like that.
What value was the resistor?