Can you have additional duty as SHARP and still be in a leadership position?

As a company representative? Or a BN Victims advocate or SARC? I'm currently in a BN role for an additional duty and still serve my primary position. The BDE for sure has to be full time. Also, if you're a BN level VA or SARC then the leadership that selected you to fulfill that role needs to know and understand that the position may require you to be pulled from work if there is a case that requires your assistance. I hope that answers the question.

Being a SHARP Rep is a "Additional Duty" just like you stated, so you can and should still hold some type of 40 level position. Now, if you are appointed as the Battalion or maybe even the Brigade Sharp Rep then this could be considered your primary job. When you are the SHARP rep at a higher echelon then this is a very demanding position and its more than just when a incident occurs. You have to conduct training to minimize the risk across the formation and even advise the Chain of Command on new and updated policies.

SFC Timmons,
You cannot be a commander or in the chain of command and still be a victim advocate at any level (meaning Program Manager, BDE SARC, or BN VA). You would be unable to accept a restricted report. Soldiers can only submit restricted repots to the Sexual Assault Response Coordinator (SARC), Victim Advocate (VA), or a Healthcare Provider (HCP). They may also report the assault to a chaplain. Although a report to a chaplain is not a restricted report under policy or the provisions of Directive, it is a communication that may be protected under the Military Rules of Evidence (MRE) 503. If a Soldier reports an assault to a commander or someone in the chain of command, that individual is required to investigate and it renders the report unrestricted. In cases where a victim elects Restricted Reporting, the SARC, VA, and healthcare personnel may not disclose confidential communications or SAFE Kit information to law enforcement or command authorities, either within or outside the DoD. This information can be found in AR 600-20 and here: http://www.sexualassault.army.mil.
Depending on the component you are in, (Active or Reserve) positions are not always collateral. I am in the Army National Guard. Because I am AGR, I'm the BDE SARC but I am also the BDE S1 SR HR NCO. My appointment as the BDE SARC is an additional duty until we deploy. Then it becomes an full-time duty position for the duration of the deployment.