Real gumbo get okra. I know some forked over Yankeefied, suburbia living, soccer watching, instant rice cooking, 30 minute roux having, cheap ass polish sausage using recipe gets cooked and served. Okra is a main ingredient. Someone who says different probably comes from a family who never beat a run a way slave. And those same beaten run away slaves who helped create the dish used okra.

Celery traditionally doesn't go in gumbo
Pork if it's not in sausage doesn't go in gumbo
Beef NEVER goes in gumbo
Filé might go in the gumbo if you want, but not needed.
Tomatos get used depending on the recipe

Keep cooking your soup