The Law Officers have standing (locus) to bring proceedings even where the alleged contempt is civil and relates to an order obtained by a private individual (para 14 of the judgment).
Jones would have been unrepresented but for solicitors and a barrister (Christopher Hames) acting for her pro bono. On this, Munby LJ said (42 and 43):
Munby LJ made no order as to costs.
It is to be hoped that government pays heed to Munby LJ's words. Anyone facing contempt proceedings (with the possibility of imprisonment) should be entitled to publicly funded representation regardless of means.