Rick, good post, and thanks.
I agree, the best option is to install some sort of "block" or cover that would act as a primary blockage to wind driven water. The Dryerjack Zero has an opening about 6" x 4". If there was enough call for it, we could create a metal cover that would hook on the hem and be supported by the PacMan mouth area, but you are the first to inquire about this. A workaround would be to cut a piece of plywood or metal that would fill or block that opening, maybe securing it with a sheet metal screw. And then create some sort of reminder tag that you would place over the control knob on the dryer that would prevent a user from turning it on until the "cover" was removed.
There are no codes that address water intrusion from roof vents. I will try some wind testing on the zero soon to see if and how wind could lift the damper. I feel if the damper would stay closed, water intrusion from wind driven would be minimal enough to not cause siginificant damage.
Keep me posted on any other findings. Thanks