Board Thread:Discussions/@comment-29900155-20171122003320/@comment-33731050-20171122045625

So long as you don't out right say that they are Iron Warriors it should be ok. Just say that they are rumored to be of Iron Warrior stock, or that their gene-seed has markers, or their Chapter culture shows similarities to the gene-seed of the Iron Warriors.

There are quite a few Chapters on the wiki that have suspect heritage and they have been considered canon friendly, so I'm sure you won't have a problem. :)