Jmjsir, I have tasted and even cooked jambalaya with tomatoes, and I like it.
Where I lived, close to Napoleanville, and where my ex's grandfather and uncle lived, in Gonzales, they didn't use tomatoes, and that jambalaya was also delicious...just different. Grandpa Gonzales did a little farming on a small patch of high ground out in the swamp, but he didn't grow tomatoes, and I don't remember anyone else down there growing them either. In fact, I don't remember people having vegetable gardens at all. All I saw was lots of sugar cane and swamp.
Perhaps tomatoes don't do well there, and that's why they aren't used in ther cooking.
As you say, jambalaya is a flexible dish, and every cook has his own twist.
It's like putting okra in gumbo. Some people insist it must be in there, but in that area they didn't use it. Again...perhaps because they don't grow it there.
Just so you know what kind of place it was, my ex's uncle told me, "Don't you let le bebe be outside without you watching...the gators might get her."
Well, I thought he was just teasing a green young yankee...until one day while I washing dishes and looking out my window. I saw an alligator about 9 feet long making his way through my yard.
You'd better believe, "Le bebe" did not play outside without me watching.