There is a way to verify a completed test has been uploaded to Pearson for marking, using the Administrator Dashboard.
Instructions showing these processes can be found in the Pearson Onscreen Platform LAN Test Walkthrough:
Pearson Onscreen Platform (POP) LAN: Test Walkthrough
Please see the section 'Uploading the completed test'
Related Articles:
Pearson Support Portal: Creating An Account
Pearson Support Portal (Staff at Centres & Associates): Creating A Case Record
Pearson Onscreen Platform (POP) Support Index