Hmm, the curtain might be a factor. Akos likely needs to be able to have line of sight to where he wants to place the grease spell.
An option is to 'peek' (and active the wand) around the edge of the curtain before moving back. (Don't need to worry about AoOs.) Akos could then place the effect at one of the grid intersections at the middle of the bed. That way, the grease would stop at the doorway.