"WTC nuclear demolition man with construction helmet in WTC-7 lobby"

This is really freaking weird:



Secret Service -- OST = Office of Secure Transport

Since the recent release of the NIST FOIA, this short clip reveals a person of questionable presence. Who is he? Secret Service Special Agent Bennette who is acting as a liaison of sorts for the Tower 7 lobby after Tower 2 has come down, but when asked his title, he states O.S.T.
Quick search of OST, (Office of Secure Transportation) reveals an arm of the Department of Energy responsible for the transportation and security of nuclear and, or "related" materials...
For further reference see their site:
https://fmt.kcp.com/OSTfederalagent/
Not some group that changes light bulbs in Federal Buildings...