Excellent video! You lights look like new afterwards! Mine failed in the same way (chrome behind the glass hemi-spheres). I could not figure out a fix so replaced them with new headlights. Surprisingly cheap at £75 each and it transformed the car.
Which Megane 2 you have? Phase 1 or 2? And did you buy them new? With Xenon? Here much more expensive (Megane 2 phase 1 Xenon) Im curious that after sticking that tape (found it online) if you have an reasonable image at all!
Does the headlight shine badly because the chrome from 5:15 is gone from reflector? The lens from reflector seems to be ok. Or is casue of the damaged plastic front cover from the sun? My friend has a Peugeot 308, his front covers are yellow like lemon but still the headlights shine better than mine. He has no reflectors tho.