Here is the crash protection link:
www.sweetprotection.com
This says 40% off, for same model, purchased within last 3years with evidence.
For what it's worth, I think just about every Helmet brand will throw you a discount coupon even if you don't have full evidence anymore, or if your purchase is older (i.e. you lost the helmet in the hospital/ambulance).
They will be very lenient to give you benefit of the doubt and appreciate your story and will write back hoping you recover; with a discount code as goodwill even if you technically don't qualify to the program rules. (it is profit to them even at 40% off, they have these restrictions up as they don't want to promote that they are in direct sales, vs supporting their dealers).
But also keep in mind the discount will just be off MSRP from them direct. It's better than paying full price; but it's not an extreme super special deal.
If you really aren't tied to exact same brand/model for loyalty, and are more really about dealhunting, you can find better deal pricing on prior years helmets that are on Sale; or if you can hold out until Spring/Summer (while you recover from your brain injury) then definitely you will find more Sales/Clearances for even cheaper