InApp Purchase in Private B2B App

I have an app that is currently in the App Store. The app contains serval inApp purchase items that work properly. Recently I created a variation of the same app for private distribution which I intend to make available to certain customers through Apple Business Manager or Apple School Manager. The single inApp purchase item in the B2B app works properly in TestFlight. However, after the app was submitted and approved for App Store distribution, the production app is not receiving localized information for the approved inApp product.

Specifically, the app is calling SKProductsRequest with the set of product identifiers (only one product) and is receiving an empty array of products in the response. As I said, this happens only ln the private B2B production app. In TestFlight the products are in the response as expected. The same code works properly in the normal App Store app.

I submitted a question to Apple support regarding InApps in B2B apps. Their response indicated that InApp purchases are allowed. Does anyone have any experience with this situation? Are inApps really allowed in a private app, or is something else going on?