In this case, fo future I would never suggest using third party software for this. I’ve edited about 100 music videos and I came to learn that there’s always a sound to sync to. Look for an “S” or “P” sound or a drum hit. Usually, a clap or a snare will work. Place a marker on the audio track and then scrub through your clips and locate that moment. Also, you need to use good converter for that https://convertereal.com/