Well first off you would need to add a command to the !8ball trigger
Secondly you can use a /load /unload feature in a seperate script
thirdly you can use a group enabler and disabler

where if !8ball == true then play, elseif false then stop

there should be a on text command in the script that executes everything its hard to know without seeing it but add this where you see the !8ball trigger

if ($2 == on && $nick isop $chan) { %8ball.status = true }
elseif ($2 == off && $nick isop $chan) { %8ball.status = false }

then the whole script should be in the middle of something like this

if (%8ball.status == true) {
whole 8 ball script here excluding the Variables...
}
elseif (%8ball.status == false) {
msg $nick Unfortunently 8Ball script is off.
}

I can't say much more then that since I dont see the script sorry