I have one of the Mouser Molext 4 pin cables. Its got a molded connector. And try as I could, even with the help of my automotive pin extractors, I could not get the pins out. I am afraid this is a dead end, unless willing to replace the plastic connector.
I did find an alternative fix though. I found a guy on etsy Joshua Cunningham that sells a 4 pin extension cable and ordered it. Got it today, checked its pin out, simply a straight-thru cable. People mentioned concerns about length of another cable presenting a frequency or signal drop problem. I have seen no problems. Been printing all day with it. He’s reasonably priced too. Shipping my be less/more to you, so I won’t say what I spent.