I don't disagree on the first point and on the second I think we are more or less in agreement regarding looking into the historicity and not arguing for the sake of it. If the historicity of those statements from Philo and the Wisdom of Solomon is difficult to prove then I clearly cannot push it further. I do find it quite interesting though.
I read a very interesting and VERY detailed article in from my Logos Bible software on Sodom and Gomorrah. Here is the summary for your consideration.
Summary
The location of Sodom and the Cities of the Plain is no longer a mystery. The Bronze Age civilization of the eastern Kikkar was very likely the source of the biblical tradition concerning the Cities of the Plain and the backdrop for the Sodom tales. The Bible represents Sodom as the largest Bronze Age city on the Kikkar of the Jordan, and this must be Tall el-Hammam. TeH was the largest Bronze Age city in the region—larger by several orders of magnitude than Jericho, Jerusalem, and every other site in the southern Jordan Valley.
The Land of the Kikkar was home to a spectacular civilization for more than 2,500 years; but all of it came to a violent termination toward the end of the Middle Bronze Age, the time of Abram and Lot. The Jordan Disk remained without cities and towns for the next six to seven centuries, and Sodom became Abel, the Place of Mourning. Joseph mourned Jacob there. Later Israelites would see the Kikkar as the place where “Pisgah overlooks the wasteland” (Num 21:20), and call it Abel ++++tim, Acacias of Mourning.
After their destruction, Sodom and Gomorrah became one of Scripture’s principal metaphors for the wrath of God. Archaeology has confirmed that the Cities of the Plain met a fiery end and remained uninhabited for centuries. If the text of Genesis does preserve factual information about this event, an explanation is possible. Toward the end of MB2, some horrific, fiery event burned up everything on the Kikkar, including cities and towns, crops, and natural vegetation. The event was remembered in local lore attributing the destruction to the locals’ gods. After several decades—or perhaps more than a century—
the area recovered its natural vegetation enough to support agricultural activity once again.
But then the folklore prevented anyone from building permanent settlements there even after agriculture again became possible. Locals saw the area as “cursed by God,” and a palpable fear kept people away, except for intrepid farmers who worked the land after the spring inundation of the Jordan.
Collins, S. (2012). Sodom and the Cities of the Plain. In J. D. Barry & L. Wentz (Eds.), The Lexham Bible Dictionary (J. D. Barry & L. Wentz, Ed.). Bellingham, WA: Logos Bible Software.
If you want to learn some more about the articles I can try to email it in a document to you, it's very good.
Be blessed!