I have successfully added my IAP along with the required metadata screenshot. On the actual IAP page it says Submit for Review
but it's grayed out.
On the page main IAP page (Manage page with the secret key), it says Ready to Submit
On the Prepare for Submission Page I have a binary uploaded and it shows my IAPs
I looked at multiple SO answers but I haven't found a concrete answer. On the IAP page, why is the Submit for Review
button grayed out? How can I submit my IAPs for review without actually submitting the app to go live?
The app itself must be submitted for approval before you can submit your first in-app purchase.
How can I submit my IAPs for review without actually submitting the app to go live?
Well, you're confusing two things. Just because your app has been approved doesn't mean it goes live to the store that day. You're allowed to specify a later date.
However, what you're positing is actually a great way to proceed: submit the app and get it into the store first, and then add the in-app purchase in an update later.