First, if you add entity_set_edict(ent, EV_ENT_aiment, id) to entity then that id will not see that ent
( Also owner was needed to set if you want to use aiment if i remember correctly )
2. if you use aiment then you cant change render stuff (EV_INT_rendermode, EV_INT_renderfx etc...)
if you do then entity will be invisible for ohter but you can see it with CAMERA_3RDPERSON view mode.