Originally Posted by ursine1

You can't request cash back from a credit card, only from a card that also has a debit card function.

If you use the Southwest Visa card to get cash at a bank or ATM, or by using the convenience checks they may send you, you'll pay a bunch of fees including a percentage of the cash amount, interest will start accruing immediately (vs 20 day grace period), your interest rate may change, and you won't earn RR points on the cash amount and it won't count towards any bonuses.