Yes I have tried them and no one has found any trace of a Catherine Ash and very little clues on James Ash as neither are in any census records. So unlikely to be duplicating anything.
The report in the Sheffield Iris of a meeting which appears to be the founding meeting of the association in 1839 does not mention a Catherine Ash. The named persons were:
chair: Mrs BROADHEAD
proposers and seconders of 3 resolutions:
Mrs BROWNHILL
Mrs SYLVESTER
Mrs Selina SYLVESTER [probably the same person]
Mrs Caroline SCATCHARD
Mrs LUDLAM
Mrs BARKER
secretary: Sarah FODEN
The meeting took place on 11 June in Fig-tree Lane, and the report appeared in the Iris of 18 June.
Found the anomaly The Females Chartist Association was formed in January 1842. I presume this is where Catherine Ash comes into it. Why they started a new group is not yet known. Certainly Mrs Foden was the wife of well known Chartist Peter Foden who was friend of Ebenezer Elliot.