I'm trying to access the values m_pGlowTrail and m_pMainGlow on creation of any entity npc_grenade_frag. Dumping the datamaps showed me that those values in fact do exists but when I try to acces them I get this error for either of them:

Now I'm wondering how I can access them (and I know they can be accessed as I'm porting a SM plugin which did).
Thanks :)