1.13 allows him to be recruited instead of killed.
Must have 70 leadership and critically injure first. Also can't be the last enemy alive when you attempt to recruit or it will glitch.
1.13 allows you to keep him forever (Enabled in INI).
1. Threaten him (so he stands up from his wheelchair)
2. Give him the disk from Carmen
3. You can recruit him (the leadership of your mercenary is not important)