Neither of these in this case was Muslim, just tangentially and coincidentally mixed up in the plot.
What is your evidence that one or both of the women is not Muslim? It looks like they are all Muslims. What am I missing?
http://www.latimes.com/local/lanow/la-me-ln-enrique-marquez-rifles-20151209-story.html
“Marquez, an HIspanic convert to Islam, married Mariya Chernykh in November 2014, according to county records. The marriage added another connection to the Farook family; Chernykh’s sister was married to Syed Raheel Farook, the shooter’s older brother.”