Whoever came up with this voucher idea must have been both brain-dead and tone-deaf. It's insulting.
Rather than even trying to offer compensation it would have been far better to just be upfront with an apology.
Example: "We are deeply sorry for our recent incident. No compensation could make up for the damage this incident caused, or the untold thousands of cumulative hours that IT professionals across the globe spent to rectify it, in many cases working through their entire weekends or missing vacations to do so. We appreciate our failure has rightly caused a tremendous loss of faith in our brand and product, but please be assured we are working on concrete steps to ensure an incident of this kind cannot happen again, and will share those plans with you soon."
I'd rather hear that, to be fair.