I don't know what good the ATF would do that oil wouldn't do better. Any gas that leaked in should have been in the pan. You've already drained that. If it was me, assuming the gas leak has been fixed, I'd just fill it with oil as usual and drive it. If it had been run with the diluted oil I'd let it idle for a few minutes to make sure everything had a coat of good oil before heading out.

Save a life, adopt a senior shelter pet.
The three main causes of blindness: Cataracts, Politics, Religion.
Name your dog Naked so you can walk Naked in the park.