Hi RoxiT,
Oh my, your poor
Fiddle Leaf Fig (Ficus lyrata) 
As a human Floridian, I can't imagine being subjected to -30ºF ... even for a very short period of time and I know a
tropical plant really wouldn't be happy with those temp's either.
I'd advise to keep it in a warm, bright location, cut back on water and
don't mist the leaves. Cold, combined with wet = fungal issues.
I wouldn't give up on it completely, plants can surprise us sometimes and as long as the roots didn't freeze, there's hope! Be very careful with watering at this time of year; when plants aren't actively growing they need less moisture.
