The offers will tell you how long they take to confirm. Generally they confirm within an hour.
If you do not provide valid information, you will not receive GoCoins. If you provided valid information and you still have not received GoCoins, you would need to contact the respective company that hosts the offer wall. The offer wall is providing these offers and confirming them. We have no control over whether they go through or not. If you do not get paid, we do not get paid.
No. This behavior will get you banned on all accounts.