Fuselage icing (hoar frost etc) permitted if only a thin layer exists, i.e. one through which surface details/markings can be seen (approx max 3mm). Maybe they had more than that?
After a foot of snowfall on the aircraft you'd need to de-ice everything, so you must have to start doing it at some nominal thickness.
Bottom line is, if you (PIC) want it de-iced (whatever 'it'is), get it de-iced. No argument.