Roger, maybe there is a glue or epoxy solution that would work. If not, there is another solution to possibly consider, keeping in mind that I don't have any actual experience with Ross switches. Anyway, here's my thought.
If you were to loosen the 4 rail clips, circled in blue (maybe they're staples) on both sides of the short rail, it appears that the rail could slide out the end of the switch. You could then file off the offending rail flange indicated by black smudges where the red arrows are pointing, slide it back into place and re-tighten the clips. This should create a sufficient gap between the rails where they meet at the frog.