Client Crash / Disconnects while Boss fights

Today i got a client crash because of killing Sirus (too fast)?
Now i get an unexpected disconnect while fighting "Mavens Invitation: the twisted". Every time i try to rejoin i get disconnected again.

So my loot is gone. I am playing a srs minion build with a lot of actions happening parallel. i dont know if that is part of the reason

Could you investigate what is happening?