Sorry for the delayed response - if the SKProductsRequest is failing, this would appear to be a bug report issue. However, the first thing I'd do is collect a console log from the Apple TV with the StoreKit profile active. I'd then include the console log with the bug report. Here's the instructions for doing so.
To install the StoreKit profile onto the Apple TV please follow these instructions
1. On your macOS system (10.12 or later) open Safari and navigate to the Developer Bug Reporting - Profiles and Logs web page
<https://developer.apple.com/bug-reporting/profiles-and-logs/>
2. Download the “App Store/iTunes Store for iOS” profile. You will see the file “itmsdebugging-2.mobileconfig” in your Downloads folder.
3. Enable Remote debugging with the Apple TV with your macOS system (see below if you aren't familiar with this step)
3a. Open the Settings app on the Apple TV - Remotes and Devices -> Remote Apps and Devices
3b. On the macOS system, launch Xcode -> Window menu -> Devices and Simulators. Select the Apple TV and follow the instructions to connect with the device.
4. On the macOS system, launch the “Apple Configurator 2” application. You can install the Apple Configurator 2 app from the Mac App Store.
Within Apple Configurator 2, select the Apple TV, then click on the “Profiles” item on the left column.
Navigate to the “itmsdebugging-2.mobileconfig” file and select it.
5. Go to the Apple TV and enable the installation of the profile - After the install is complete, restart the Apple TV.
To access the Console from the Apple TV, open the Apple Configurator 2 app, select the Apple TV and click on the “Console” item on the left side.
Clear the console log, then start your application.
6. When the issue occurs, save the contents of the Console log
Check the contents of the console log for the string “fetchSoftwareAddOns”. If this string is not present in the log, the profile was not active. Please re-install the StoreKit profile and make sure to restart the device.
Instructions to enable Wireless Debugging
Requirements - Xcode 9.0 or later on macOS 10.12.4 or later
Requires tvOS 11.0 or later
Both the macOS system and the tvOS device must be connected to the same WiFi network
To set up the Apple TV
1. Launch Xcode - choose Windows -> Devices and Simulators, then select the Devices item
2. On the Apple TV, open the Settings app and choose Remotes and Devices -> Remote App and Devices. The Apple TV searches for
available devices to connect with.
3. On the Mac, select the Apple TV in the Devices pane. The Apple TV pane is displayed with the current status of the connection request.
4. On the Apple TV, note the verification code, and enter the code in the Apple TV pane on Xcode. Then click connect.
Xcode will set up the Apple TV for wireless debugging.
Submitting a Bug Report
To submit a bug report for investigation by iTunesConnect, please use the Apple Developer Bug Report web page - http://bugreport.apple.com.
After logging in, select the Product “Other”.
Fill out the bug report form. In the description section -
make sure to include the application ID
add the in app purchase identifiers which are failing
Please include the console log contents
By following these instructions, the Bug Report team will be able to expedite the assignment of the bug report to the iTunesConnect Support team.