The input shaft looks like it got hot. I had an issue like your mentioned with a needle bearing cup input shaft bearing on my pickup. Truck would not go in first or reverse when the engine was idling.
I'd clean and polish that input shaft with a very fine sandpaper as per or crocus cloth to make it very smooth and polished up. Grease up that input shaft bushing. Do not use a lot of grease. Since it can spray out and foul up the disc. Bolt it back in and try it again.
As far as the Z bar goes. Probably find the one that fits correctly and install it. For such short miles on a relatively new clutch, that's certainly a lot of wear and heat checking on it. Do you drive it with a heavy foot on the clutch?
