Ok found it the issue was with Sindae's Texture pack (yes mods were off, apparently the issue stuck around if you didn't leave the game)
Larian left a blank glow map
<node id="Texture2DParameters">
<attribute id="Enabled" type="bool" value="True" />
<attribute id="ExportAsPreset" type="bool" value="True" />
<attribute id="GroupName" type="FixedString" value="01 Texture Map" />
<attribute id="ID" type="FixedString" value="" />
<attribute id="ParameterName" type="FixedString" value="Glowmap" />
</node>
and she removed an ID from a texture she wasn't using, boom blank glow map is applied to illithid heads.
<node id="Resource">
<attribute id="Depth" type="int32" value="1" />
<attribute id="Height" type="int32" value="256" />
<attribute id="ID" type="FixedString" value="" />
<attribute id="Name" type="LSString" value="ClothSecondary_KEL" />
<attribute id="SRGB" type="bool" value="False" />
<attribute id="SourceFile" type="LSString" value="Generated/Public/SindaeTexturePak/Assets/Textures/ClothSecondary_KEL.DDS" /> MSK
<attribute id="Streaming" type="bool" value="True" />
<attribute id="Template" type="FixedString" value="ClothSecondary_KEL" />
<attribute id="Type" type="int32" value="1" />
<attribute id="Width" type="int32" value="256" />
<attribute id="_OriginalFileVersion_" type="int64" value="144115207403209024" />
</node>
Mod is updated.