Damaged a new coil pack

Hello, there is no definitive answer from here; just your hands on experience that you have and the knowledge that whatever happened -- as long as you didn't accidentally mix up coil packs -- something compromised the "known good" coil. Ultimately, sure, problems with the vehicle that has the random misfire code (P0300) could be damaging to the coil. But it's all a guess. Did you try the coil off of the misfiring vehicle on the "good" vehicle? I'd be curious if it malfunctions there? Swapping "known good" parts is a diagnostic process that some use to a degree of success. But a diagnostic tool with capabilities of checking ignition system components, engine relative compression, cylinder misfires, component operation is essential in the diagnostic process. I'd recommend seeking guidance from someone of experience, skill and knowledge that has such equipment.