Mirkovic's two turnovers occurred at the 8:15 mark in 1H and at the 15:19 mark in 2H.
First one, he slipped and fell down..
Second one, unsure if its the one you're talking about, but it sounds similar... in transition, he throws a pass to KB who is in the corner, KB got both hands on the ball and drops it out of bounds.. now, it wasn't the most on-target pass ever but it was certainly catchable.
Here's the clip:
So as to how the accreditation works: a missed catch on a pass results in a turnover charged to the passer no matter whether the receiver touches it or not, so the player who passes the ball is charged with a turnover even if it was the receiver at fault.
EDIT: I'm unsure why the rule/accredition works this way, but that's how it is scored. If I had to guess I'd say they just charge it to the passer so as there is a hard and fast rule as to how to score it and you're not relying on a judgment call in every scenario.