Killion lost in the first round 6-4, 6-2 to Melissa Shank of Osage.
Killion stayed alive in the consolation bracket with a 6-1, 4-6, 7-5 win against Felicia Owen of Jefferson.
Killion was eliminated in the consolation quarterfinals when she fell to Cameron's Jennifer Salmon 6-0, 6-0.
Also competing over the weekend was Charleston's doubles team of Megan Luehmann and Claire Showmaker. The pair went 0-2 on the trip.
They lost in the first round to Ladue's Kelsey Brendell and Leila Seymour 6-2, 6-1.
They were then eliminated in the consolation round by Chillicothe's Devon Doss and Anna Uhlitz 7-5, 1-6, 7-6 (4).