Originally (OEM & early replacement parts), that sleeve was solid and would have been machined - back in the day when things were made to a quality standard. And for GTS bushes the sleeve was slightly thicker so there was less rubber, making the bush a little bit stiffer.
Now they look to be pressed, no doubt because the process is quicker and cheaper- these days stuff is made to a price, and the cheaper the better as far as manufacturers are concerned!
The Mackay and Rare Spares bushes are made exactly the same way these days and the reality is they are probably all made in the same PRC factory!
Kingswood Country may well send a replacement set, or even give a refund but I'm tempted to believe you will only be shifting the problem to the next set you try,
and buggering up your suspension arms in the process.
Obviously the bolt should go through, but it should be a neat fit, as its job when tightened up is to hold the centre sleeve firmly in place with no movement. The sleeve is not meant to be turning on the bolt; the rubber bush should be doing all the work.
So, given it sounds like the bolts 'nearly' go through, I would be assembling them and tapping the bolts through as gently as is possible. The suspension all needs to be tightened up when it is in its normal 'at rest' position, so this may have to wait until after the vehicle can do a lap around the block.
My thoughts on the problem :-)
Cheers,
JPXU1