I went to a local home improvement store and they only had 2 products capable (according to the teenager working there...) of fixing the FG balcony.
One of them was a 2 part liquid. Cant tell exactly what it is but I believe it is some kind of resin that once mixed will cure and harden. The instructions recommended to sand the are to repair with a 80 grit sandpaper.
The FG cloth was sold separately.
The other product was more or less a all-in-one kit with the 2 parts liquids, the FG mesh, a spatula, etc..
Whatever I end up using, it needs to be very close to the original deck color (light clay/grey color) and shouldnt show up as a thick layer which will be apparent...
Ideally, since the deck is neither perforated or broken thru, I think only a resistant resin to fill the hairline crack in the gel coat would do.