These are the options I used to install the SCCM agent on Workgroup or Azure AD computers
ccmsetup.exe /source:PathToFolder:\SCCM /NATIVE SMSSIGNCERT=PathToFolder:\SCCM\SCCM_WORKGROUP.cer /skipprereq:vcredist_x86.exe /UsePKICert /NoCRLCheck FSP=dmz.domain.com CCMALWAYSINF=1 CCMFIRSTCERT=1 CCMHOSTNAME=dmz.domain.com DNSSUFFIX=domain.com SMSSITECODE=ABC