No, the workflow to reserve and commit a translation is as follows:
1 - Reserve the module
2 - Upload the translated PO file
3 - Review it (no need to previously reserve it for proofreading)
4 - Mark it as "Ready for submission"
5 - Submit the PO file to the repository
The "inform of submission" option just sends and e-mail to the translation team mailing list to notice the file has been uploaded, but it directly doesn't commit the PO file into the repository.
Also note that you can assign different roles to your team members. The roles tha have commit rights are "commiter" and "coordinator" so you, as coordinator of the team, can commit your translations yourself, or you can delegate this task into another (commiter) member.
