Q. Is it permissible to arrange a shidduch if it is possible that the couple isn't religious enough to keep Taharas Hamishpacha?
A. Many Poskim maintain that there is no prohibition on arranging, helping or being mesader kidushin (performing the wedding ceremony) of a couple that does not observe taharas hamishpacha (family purity laws). Many require that the couple should commit to at least go once, prior to the marriage to the mikvah. (Minchas Yitzchok 1,10 – Chelkas Yaakov 1, 23 - Sridey Eish 2, 57 and 3, 28 – Hapardes year 13 vol. 5,7, 11 and year 23 vol.1 - Hilel Oimer Y.D. 67 - Hashavit Y.D. p.167).
Rabbi A. Bartfeld as advised by Horav Shlomo Miller Shlit"a