Remember Oxygen is already dissolved in the solution, so unless you're bubbling nitrogen through it to de-oxygenate it you're going to burn up all of the oxygen scavenger in liquid form far before the O2 starts making it across the thin film.
It'll help, but more importantly- don't mix it until you need it.
Nitrogen is normally used because it is inert, so is argon, you should be OK. Aside from the liquid air junction, these fluids contain dissolved gases, which incudes oxygen. Nitrogen or argon, should act to lengthen the shelf life of stored chemicals. However, father time works it's dirty deed.