Coil pack damage not my fault

What is your question?

What could damage the coil pack on my 2006 durango. to give you what happen, I had my oil change from a oil company,a few days later.....my truck starter to shake. I went back to the oil company,and they told me that the oil damage my engine,and they will replace it....but the coil pack is not apart of the motor. I had no problem with truck before this happen. why did the coil pack go bad?