White glue or matte medium for securing ballast?

[videobruce]

A product that " turns only the rail rust color ", while gluing the ballast ?? --- Now there's something I would definitely buy !!

Here are pics of the track/rail in question (Atlas code 80) and a section of Peco code 80 behind it.
Granted, the example is 15 years old and I'm sure it has 'tarnished' more since then, but you can get the idea what I'm talking about. The last photo shows it best.