Probably yes, one factor that give them money and i think it's untraceable transaction that going to their fund.
They may be getting some of their funding in the form of Bitcoins (and the other crypto-currencies), but I am sure that the proportion may be very insignificant. Even if they get the Bitcoins, how they are going to spend them? I am not sure whether the arms smugglers and farmers of Syria accept Bitcoins. Even if they do, the markup will be very hefty.