It sounds like the machine wasn't packed properly. I used to sell vintage sewing machines and in order for the machine to arrive in 1 piece, you need to bubble wrap them to death,
double box the machine and case, use solid styrofoam in the outer box. If any thing rattles its not packed properly. When boxes are handled by the various shippers, they drop off a conveyor belt and its a 5-6 foot drop. I've sold/packed many machines and never had one damaged.
Good luck with your damage claim.
Sharon W.