According to this “the extension will only render if the app that is associated with the extension, is also the “owner” of the product. In this case that means has also created the associated bundle.” During dev this is done by creating the product using a local instance of the GraphiQL admin api. I’ve created an extension only app and one of the extensions is this type of admin ui extension. So how would one accomplish this on a non-dev store, meaning the store the custom app is finally installed on? Just creating the bundle product with the installed Shopify GraphiQL App makes Shopify GraphiQL App the owner.
Ended up making an Admin Action Extension for the products index page that gives the admin an interface to create bundle products. It seemed the only way. Was planning on that being a future feature for the client. Ended up being a needed feature.