The resin for the DLC armor not having a helmet toggle option is the way
the armor mesh is coded in the games ini files.
All the independent armor parts go to the N7 custom armor.
i.e. FullBodyAppearances=(Id=61,Type=CustomizableType_Torso,Mesh=(Male="BIOG_HMM_ARM_MED_R.MEDb.HMM_ARM_MEDb_MDL",Female="BIOG_HMF_ARM_MED_R.MEDb.HMF_ARM_MEDb_MDL"),GameEffects=("SFXGameContentDLC_PRO_Pepper01.SFXGameEffect_Gear_Pepper01Helmet","SFXGame.SFXGameEffect_Gear_N7Torso","SFXGame.SFXGameEffect_Gear_AmplifierPads","SFXGame.SFXGameEffect_Gear_LeftArmAmmoPack","SFXGame.SFXGameEffect_Gear_StimulatorConduits"),PlotFlag=-1)
like the cerberus armor
vs
TorsoAppearances=(Id=4,Type=CustomizableType_Torso,Mesh=(Male="BIOG_HMM_ARM_MED_R.MEDb.HMM_ARM_MEDb_MDL",Female="BIOG_HMF_ARM_MED_R.MEDb.HMF_ARM_MEDb_MDL"),GameEffects=("SFXGame.SFXGameEffect_Gear_N7Torso","SFXGame.SFXGameEffect_Gear_AmplifierPads","SFXGame.SFXGameEffect_Gear_LeftArmAmmoPack","SFXGame.SFXGameEffect_Gear_StimulatorConduits"),PlotFlag=-1)
Default custom N7 Torso
I think this changed from the way it worked ME1 because of the
custom N7 armor and the way it is hardcoded in the game's files.