Interesting question. I do not apply wake turbulence separation between medium/light when having paralell operations from FATO and RWY (distance between is approx 150m), and none of my collegues do either. This was up for discussion at my unit when FATO was established, and it was concluded that 4444 5.8.3.1 does not apply in this situation. Departure direction from our FATO is perpendicular to the RWY, and can in no way be interpreted as parallel as is a prerequisite for 5.8.3.1 to apply.
I will however caution of wake turbulence if there is crosswind together with traffic information if the winds are such that wake will blow towards the light.