However, both 587VS and 447VS retained the Rudder through water impact. 587's Rudder separated while in the water, suggesting it had endured greater Yaw induced damage of the Rudder hinge. Remember, in a separation at altitude, in a Yaw sufficient to cause separation, the relative strength of the Rudder hinge in both cases is patent.
It is reasonable to assume some retained lateral velocity, if what is suggested is separation at water impact, yet the VS/Rudder is almost pristine. I suggest this is indicative of a quick failure at high speed, leaving the VS/Rudder to find its own aerodynamic descent method. In most cases, its shape ends up "leafing" down, rather than edge on at higher speed. This would be consistent with the lack of wrinkling or folding of the assembly when found. Conversely, the spoiler would have endured its massive destruction while attached; after separation, its descent would have been gentle, consistent with the large surface area/weight like the VS.
bear