ChefDean and Panman are both knowledgeable about growing CPs, I'm not familiar with Inter and Fly, but he probably knows a bit, too.
Give them time and good lighting and keep the grow mix moist...they should turn the corner by the first of the year.
Lots of people don't rinse the ingredients for their grow mix and the plants do well for them. I rinse mine before using (I refer to myself, at times, as "OCD-Me"
). By rinsing I can lower the TDS level in the soil (measured in the drain water) and reduce the algae/mold growth on the surface of the peat moss. As for the perlite, sometimes it contains "other" things...salts of some kinds, I've heard it mentioned. What I've found when rinsing is that there can be a bit of a sludge of fine particles in the bottom of the bucket...this approaches mud consistency. Also, the drain water is a milky white.
I don't rinse to a pristine, clear drain water but will rinse a couple of times. You may have done all of this and maybe not. It probably doesn't help/hurt anything...but I feel better doing it.
Just thought I'd mention this.
I think, though, with time they will be fine...in my newbie/amateur view.