Second time this bug happens for me and my friend. Sirius is stuck floating in the air infinitely ruining the whole fight for us. Now we were farming to get into fight with Sirius for 4 hours both times. Its getting really, really frustrating. I understand that you guys are working hard on bug fixes, but bugs like this should be refunded somehow. Because at the moment it feels like a complete waste of 8 hours. The league at the moment feels totally unrewarding with all this bugs in Sirius fight.
Thanks for your report, this will be fixed in up upcoming patch, you can find the patch notes here