I assume that HaRav Neiman would say even necessary conversation soley pertaining to work related issues, with a woman is bdieved. However for parnassah its very often not possible to do the lchatchila, especially when it comes to dealing with women. Since R Neiman views it as a necessity to at least talk about work related issues, he is matir it.
I was merely suggesting/wondering that his heter should extend. I am saying that in order to keep a job in a standard office environment one must make small talk with women as well.