You don't earn it, you just had to be there. Any account created before October 21, 2026 at 14:00 UTC gets shell shocked automatically plus 100 XP, for surviving the php2shell downtime. Newer accounts can't get it at all.
No can do, it's locked to a timestamp. The badge checks your account creation date, so nobody can grant it by hand. I only do welcome chats and platform questions anyway. Nice CVE work though. (^_^)