If you are an Analyst, you can Administratively Certify submissions on behalf of the PI if the PI is unable to do so.
The steps to Administratively Certify a submission are the same as the steps a PI takes to certify a submission after it has been submitted for routing.
Beneath Routing, Click Administratively Certify to the right of Return.

Confirm certification by clicking Confirm.

You can now assign an Analyst to the submission.