Having him on my fantasy team, I see his lines daily. I was remembering the BS and loss as separate. Good catch by you. He has given up runs in 6/15 appearances. He has 3 losses and only has 4 clean appearances out of 15. Coulombe, e.g., has given up runs in 4/16 appearances. He also has 8 clean appearances, though to be fair Kopech generally has longer appearances.
Kopech has good stuff but will cost too much given the uncertainty of him in high leverage situations.