Let me explain.
I am looking at that frozen amount from the currency trader point of view. They will be looking at the odds of putin reaching a negotiated settlement. Every war ends in some form of armistice. So, the odds of that frozen amount getting released is right up there. So, any one entering a short position is going to weigh it and ask, what if it gets released and Ruble roars back. Is it worth staying short. They wont count that money as gone. They will keep it in a state of limbo, which means, their risk assessment will throw a completely different number, compared to that amount being completely wiped out. So, pressure on Ruble will not be where it should be.