Nice vids. I couldnt find any spec on the #1`s either, its strange they list everything but that one. I guess they have lower flow rate than a #5 with the same head and air pressure so they may be doing less than 1.2LPH. The low temperatures may be allowing the 10 minute pause or perhaps the droplet size is smaller than ideal if its hanging around for more than 3 minutes. You should need a lot more than 200ml of nutes a day for a 288L chamber
The root movement during the misting is a clue, the portions of the roots in the direct path of the mist seem to be doing better than the roots that get diffused mist. The direct mist contains most of the larger droplets.
The nozzle looks to have a decent amount of throw at 40psi, the pattern is quite narrow which could make covering a 4x4 chamber with 2 nozzles interesting but it should widen with lower air pressure. It might be worth comparing the #1`s mist pattern and throw by temporarily lowering the gravity feed height to 600mm and running 20psi air.