Togo - //Perhaps in view of the fact that it is a RC school, and the boys mother is described as a single parent, means that her profile doesn't fit either. //
That is another sweeping and utterly unfounded observation.
two of my daughters have been single mothers with children educated in Catholic schools, my wife has been a teacher, deputy, and head teacher in Catholic schools and now works as an OFSTED and ISI inspector and their combined experience concludes that there is never even the remotest bias against single parents in the Catholic sector.
You appear to be in danger of following the knee-jerk press reaction to this incident, and seeing shadowy backgrounds to the implementation of a school policy that simply do not exist.