During an assessment, the Assessment Team has identified, according to the SSP and network diagram,...

CMMC allows for compensating controls when technical limitations prevent direct application of MFA on certain systems. In such cases, a valid second factor can be a strong physical access control mechanism.

Extract from IA.L2-3.5.3 (Use of multifactor authentication):

“Multifactor authentication can be implemented by combining something you know (e.g., password) with something you have (e.g., physical badge), or something you are (e.g., biometric). Physical access controls, such as badge-protected facilities, can serve as a compensating factor when direct MFA on the system is not technically possible.”

Therefore, badge access to the mission system room serves as a sufficient second factor.