Mouse pad?
Have you checked the underside of the mouse too? Sometimes even a hair gets in the way of the "eye", causing erratic behavior.
I'm surprised that an optical mouse could be affected by the cleanser, unless perhaps whatever they used made the surface more shiny. If the surface is too shiny, or has something like stripes for instance, it can cause strange behavior too. (Never seen striped formica... that comment is just a reflection of the fact that my Ti is sitting on a striped placemat right now and the mouse does NOT cope well with the stripes!)
I'd try good old dish detergent and water and see if that helps. Otherwise, either tape a piece of paper to the desk or use a mouse pad.
