Update my end - Commerce Account now approved.
So I didn’t have to do much other than contact them and explain that I had thoroughly reviewed the commerce terms and was confident my account didn’t breach any and that many other users seem to have the same issue. I also attached screenshots of the various screens showing the account not approved.
Here is the link the support team gave me to use to specifically contact the commerce team: https://www.facebook.com/commerce_manager/onboarding/support/?ref=cm_onsite_onboarding_channel_selection
When you click through to the link it’ll ask you to select the page you need support with. Under Topic I selected ‘Account Setup’ and then ‘Getting approval for Instagram Shopping’. I think you can select other categories and get the same outcome though so have a look through them.
My advice would be to message facebook directly using the above link if you haven’t already. Be detailed, and demonstrate confidence that you meeting the commerce account criteria.