After viewing at the code with a special search program I found out that it seems like the rudder LOD ( or stabilizer ? ) of the KA-50 as well as the KA-52 was never included in the code of Allmods. Same goes for the rotor mast.

I found this LOD entries in eech_all_mods.nsi:

KA-50:

602 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA50_HOKUM\KA_50_FUSELAGE_LOD1.EEO"
603 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA50_HOKUM\KA_50_FUSELAGE_LOD2.EEO"
604 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA50_HOKUM\KA_50_FUSELAGE_LOD3.EEO"
605 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA50_HOKUM\KA_50_LT_LOD.eeo"
611 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA50_HOKUM\KA_50_NS_LOD.eeo"
612 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA50_HOKUM\KA_50_RT_LOD.eeo"

KA-52:

621 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA52_HOKUM_B\KA52_COPILOT_DOOR_LOD1.EEO"
623 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA52_HOKUM_B\KA52_FUSELAGE_LOD1.EEO"
624 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA52_HOKUM_B\KA52_FUSELAGE_LOD2.EEO"
625 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA52_HOKUM_B\KA52_FUSELAGE_LOD3.EEO"
627 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA52_HOKUM_B\KA52_PILOT_DOOR_LOD1.EEO"
628 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA52_HOKUM_B\KA52_LT_LOD.eeo"
634 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA52_HOKUM_B\KA52_NS_LOD.eeo"
635 File "${EE_3DOBJ_DIR}\cohokum\3ddata\objects\KA52_HOKUM_B\KA52_RT_LOD.eeo"

I don't know what this exactly is for, cause I'm no coder, but as far as I'm able to construe this it looks like that different LOD-files for the rudder ( and rotor) for both helos are missing. I think that those LOD-files are still in original state and this is the reason why you get the same texture at the rudder if you zoom out for both helos.

I have no idea how I could fix this? Only way could be always to use the LOD-hack (performance?) or both helicopters have to use similar textures (not realistic).