Poor baby Koda...I would take in another stool sample to the vet just in case...tell them Koda's symptoms. When they test the stool they don't test for everything...that happened to Izzy when we got her...the breeder had her tested and came out fine but when I took her to my vet they did another test and found out she had something else but they had to test specifically for that.
Hope Koda gets better soon.