Could you cu and glue in the gab a piece of styrene plastic, painted black?
I am not sure what I would glue it to.
That is the guidance that I am looking for.
Maybe a drop or tow of hot blue would do the trick.
it might stick to the tie enough to stay in place, and hold those tips apart.
If they would, simply, bevel off the corners of those rail flanges, at manufacture, the problem would be solved, and they would never come in contact.