
In this crop from Zapruder we see Millican stood in front of the lamp post. To his left is a woman in a dark dress with a white belt. To his right is a woman in a white blouse and a dark-coloured skirt (possibly dark red). To her right is a woman in a long dark jacket with a lighter skirt.

In this pic we see Millican stood in front of the lamp post with the same women.

Again, Millican stood in front of the lamp post. In this pic his legs are slightly spread and it seems pretty obvious he is wearing trousers.
In all these pics Millican is stood in exactly the same position surrounded by the same women.
There is no doubt it is A J Millican.