If you choose the Restricted Reporting option, then your report goes no further than the SARC. You will be given a copy of the DD Form 2910 (Victim Reporting Preference Statement). This form documents that you made a Restricted Report. The SARC will keep a hard copy for 50 years, but it is important for you to maintain a copy as well, as it can be useful for accessing services and benefits later on.
The SARC is required to notify the commander that a Restricted Report was made to ensure the commander has situational awareness of their command, but will NOT disclose any information that might identify you, and they are prohibited from taking the information shared and initiating an investigation to try to determine the identity of the victim.