When you get brain damage that changes your behavior, it's for all intents and purposes 100% environment.
The brain responds to brain damage, an organism is not static. There will be epigenetic and neuroplastic responses.
"for all intents and purposes"
quoting yourself doesn't change anything.
You could easily say "for all intents and purposes" that being abused as a child is purely nurture, but that doesn't make the statement any less wrong.