I find that dryhopping at 65-70 degrees works faster to give hops flavor and aroma, while at kegerator temps it takes a bit longer. At room temperature, I find that in about 5 days I have peak flavor and aroma, while at those fridge temps it might be 10 days or so. But I keep the hops in the keg the whole time, at fridge temps without any grassiness or off flavors at all, so I think that's a bonus!
I don't think carbonation interferes at all, but what might be happening is purging the keg can "blow off" the hops flavor and aroma, too, with the excess co2.
You could try it both ways- keep the keg at room temperature for 5 days before putting it in the kegerator and see if you notice a bigger hops aroma or not. And the next time, just set it right in the kegerator for 10 days. See which you prefer!
Broken Leg Brewery
Giving beer a leg to stand on since 2006