Are you sure on the age? The outer tub halves are held together with spring clips, and far as I've been made aware the Alpha platform which debuted more than 6 years ago have the tub sealed together as a unit ... unless I'm misunderstanding on that.
Anyway, I've read of two cases (of Alpha platform machines) reported on another discussion board (and a few others found via search). One (or both?) of those involved one of the tub counterweights coming loose, or breaking off from the impact of tub oscillation.
Yes, contact WP. They need documentation of ALL these incidents.