I could really use some help getting my Instagram app approved

Question

I have been attempting to setup a website for my company that has a DTG (Direct To Garment) printer, so that eventually after the site is completely set up, people will have the ability pull images from their Instagram account (as well as Facebook), to have printed with us.

The site, www.fanemb.com/lumise (right now it's in a subdomain, eventually it will have a completely different domain name), is developed in WordPress and utilizes a plugin, Lumise, to offer a page that has a design stage, with different shirts/hoodies, that people can design their own apparel on.

Long story short, I've been able to get a Facebook app approved, with the user_photos permission. I cannot seem to get the Instagram app approved. Whenever I submit it for approval it get's kicked back. In the Lumise plugin settings, an area to enter my Facebook APP ID, which I've done, and that gives me no problems. There's another space labled Instagram API. I put in my Instagram APP ID there, even though I'm assuming that's not what it's looking for. If I just leave that area blank, then the Facebook for Developers review team can't see any Instagram Login button...so it get's kicked back. If put the Instagram App ID in there, the login button appears...but after going through all the steps to log in through the authorization window that generates, I get a message like this:

{"error_type": "OAuthException", "code": 400, "error_message": "Invalid response type: token"}

So then it get's kicked back for that reason. Basically, I'm just completely confused. I don't know how to fix this.

I've been told by the Facebook For Developers reviewers that all I need is Instagram Basic Display.