All vehilces in config.bin/CfgVehicles have their faction written in uppercase (e.g. "OPF_F")... all, except one little indomitable Gauls guy, namely the vehicle "I_GMG_01_A_F" with a faction of "Ind_F".
The faction in config.bin/CfgVehicles/I_GMG_01_A_F should really be "IND_F".
Read/Parse the config.
Maybe try to fill buckets of vehicles, one bucket for a faction each, and you might see how such irregularities easily lead to problems (yeah, yeah, I know of toLower/toUpper..., but one could also just fix it, eh. :)
Similarly "arifle_MX_Aco_pointer_F" in weapons/respawnWeapons on the class "B_Soldier_support_base_F" should read "arifle_MX_ACO_pointer_F" (note the uppercase "ACO") as anywhere else/or as defined in CfgWeapons.
Same thing for "arifle_MXC_Aco_F" on the class "B_officer_F" which should read "arifle_MXC_ACO_F".
...actually all references to/usages of "ACO" should be in uppercase, including: "CfgWeapons/optic_Aco" and "CfgWeapons/optic_Aco_smg". Oddly enough "optic_ACO_grn" is fine again/already.