So after some further testing, I have at least got some more information.
I am using NVidia's Shadowplay to record gameplay video.
I tested cutting a clip that I recorded months ago and it still cuts fine. After that, just the act of dragging and dropping one of my new clips into Bandicut crashed the application.
I've adjusted some settings in Shadowplay, like bitrate etc. Is there something known that would cause this crash?
https://youtu.be/-9XAgMgP2hY
After further testing, the older videos also crash as well. Just not every time.