1 Sodom and Gomorrah were not destroyed for what happened at Lot’s house. Their evil preceded that event.

Genesis 18:20 Then the Lord said “How great is the outcry against Sodom and Gomorrah and how very grave their sin! I must go down and see whether they have done altogether according to the outcry that has come to me; if not, I will know.”

2 The authors of Genesis do not name the sin of Sodom and Gomorrah.

3 The authors of Genesis do definitively define righteousness in this story as manifest through hospitality to strangers.

Gen 18 The Lord appeared to Abraham by the oaks of Mamre, as he sat at the entrance of his tent in the heat of the day. 

Gen 18 The Lord appeared to Abraham by the oaks of Mamre, as he sat at the entrance of his tent in the heat of the day.  Gen 19 The two angels came to Sodom in the evening, and Lot was sitting in the gateway of Sodom. 

Gen 18 The Lord appeared to Abraham by the oaks of Mamre, as he sat at the entrance of his tent in the heat of the day.  Gen 19 The two angels came to Sodom in the evening, and Lot was sitting in the gateway of Sodom.  Gen 18 When he saw them, he ran from the tent entrance to meet them, and bowed down to the ground. 

Gen 18 The Lord appeared to Abraham by the oaks of Mamre, as he sat at the entrance of his tent in the heat of the day.  Gen 19 The two angels came to Sodom in the evening, and Lot was sitting in the gateway of Sodom.  Gen 18 When he saw them, he ran from the tent entrance to meet them, and bowed down to the ground.  Gen 19 When Lot saw them, he rose to meet them, and bowed down with his face to the ground. 

Genesis 19:27-28 Abraham went early in the morning to the place where he had stood before the Lord; and he looked down toward Sodom and Gomorrah and toward all the land of the Plain and saw the smoke of the land going up like the smoke of a furnace