Where in the hell did you get that piece of disinformation, and what good would 200 more mouths to feed be for Major Anderson? He was being starved out not shot out.
You are going to be very disappointed when you find out what I have told you is true. The troops were originally on the USS Brooklyn, and Buchanan thought that might look a little too warlike, so he ordered the troops transferred to the Star of the West so they could be sneaked in quietly. Unfortunately, Confederate sympathizer ships saw the troop transfer in mid-ocean and they headed for port where they informed the authorities. So they knew the Star of the West had troops on it when they fired the warning shots.
And no, Anderson wasn't starving in January of 1861. He was still being supplied by the locals in Charleston at that time. I think it was when they found out about Fox's plan in late March or early April that they stopped supplying him with food.
Also, the Star of the West contained provisions as well as troops.