I just got off the phone with Colt customer service.
They informed me that they are aware of the issue. It is fixable at home by taking various grades of sandpaper / emery cloth and reducing the amount the knurled end protrudes. Just remove material until it no longer sticks. Apparently that is all their service department is going to do if you mail it to them... so you can save yourself the time and resolve the issue at home.
The knurling serves no function other than assembly. (To counter hold the rod while torquing the internal set screw). Newer KC’s have an Allen Head machined into the end of the ejector rod for the counter hold now... so I guess the knurling is astetic only at this point. And serves to functional purpose to the owner or assembly team.