The FBI isn't going to provide a fake ID - but it won't be necessary for him to have one, as he'll have a more generic FBI ID anyway. The "Pilot" designation is for their records - he's on payroll and in the system as a member of R&D, but he's not an agent and so doesn't have a badge or anything. The FBI will support getting him inside, though, so getting in won't be a problem for him. Anyone he wants to take with him he'll need to talk fast with his supervisor for: if they're an LCU student or other pilot it won't be much of an issue, but an unrelated party may take some convincing.