It happened more than once. When you talk to kadala right after closing greater rift, game crushes.
it doesnt “crash” for me but it does “freeze” until someone else starts another GR. The best way to avoid the “crash” is to wait before talking to kalada when the greater rift/rift closes completely.
İn fact it is the same . İ said crush because of lack of english 
but i generally play solo and there wont be anyone to open a new grift. As you said best way is to wait some time before talking to kadala but this is still an issue for blizzard to take care i think.