Fix some coupon insert hooks + prevent notices

Hey Pippin,

Not sure if you want me to create a issue for this, if so let me know.

I've made this PR to solve the following:
* To prevent some notices (when `$details['name']` or `$details['status']` is not set)
* Main reason; The code filtered `$details` while `$meta` are the used values

Hope it helps!

Cheers,
Jeroen