The accelerometer on the ST multi may work. Its quite sensitive so YMMV. I tried using it to detect door knocks, but it also detected my neighbors slamming their door… I have a shared wall with them, so it makes sense. I do have one taped to the Ding plate of my door bell and that works perfectly. All in all it does a good job of detecting vibration, so it should work for your use case.
Sounds good - the multipurpose sensor right? I can’t work out how to get it to monitor vibrations, not just open/close/temp/humidity etc - documentation is rubbish!