Not being there to know all the details, see the issue, look at adjustment slots etc, I'm only going by my own, which I have adjusted.
A suggestion would be to run slide all the way in, until it fully stops. Look for anything that may be in the way, to not fully open. When fully retracted, check gap outside. Now run it out, listening for anything not normal, and watch closely, each side, for start same time, stop same time.
How do you plan to adjust it? Have you watched any YT videos? I ran mine in part way, to kind of balance the weight, before pushing to adjust. May not be necessary on a lighter slide? Anyway before changing anything, mark where it is right now.
Hope you get it figured out.
Jerry