Thanks!
Sometimes images can help a lot…
It seems that you clamped the rear rotor not correct.
The distance from the outer edge of the hub to the bottom of the four freewheel notches is in your case about 4,6 mm - is that correct?
But it should be around 2,8 mm!
This is caused by the thickness of the brake rotor - it was not rotated correctly into its position at the corresponding profile of the hub.
You just need to open the freewheel again, rotate the rotor until it engages into its foreseen position and then tighten the freewheel - you win 1,8 mm and the frewheel won’t any longer get in touch with the frame.
Am I right?
Btw - you choosed the right rotating direction of the rotor - even if it doesn’t have a rotation arrow like the front one 
Good luck,
Chris