Deoxit is fine for all open contacts, all the PRO audio guys use it. the D-5 is more for conditioning,,,after cleaning.
I use 91% Alcohol first. NEVER use anything abrasive. You can use a burnishing tool if you have one or can get one. I used to be an IBM computer tech and I have a few left over.
It will not fix contacts that are badly worn or out of adjustment. You may need a new switch installed.