I quit direct tv. The cable company said they will pay the early termination fee. Direct tv has taken part payment from my credit card. Is that legal?

What does your agreement with direct tv say?  Does it authorize direct tv to take fees directly from your credit card?  If so, it can do so; direct tv is not a party to, and is therefore not bound by, your agreement with the cable company.  Presumably, if the cable company agreed to pay the early termination fee, it will reimburse you for the amount paid from your credit card.