The bottom line is that if you’re doing kiruv, and someone expresses real interest, you do a little asking, gently and diplomatically. If there’s any doubt, consult a rav who is experienced in kiruv with the group the person belongs to.
Something else to think about regarding geirim. Some non-Jews are interesting in Judaism but don’t know how to go about converting, so they are attracted to a Jewish man or woman. Sometimes this works out – the non-Jew’s interest in conversion sparks the Jew’s interest in teshuvah. Sometimes it’s a disaster, because the Jew is marrying out to get away from Jewishness.
In any kiruv process a situation may crop up where you need guidance. NJOP (National Jewish Outreach Professionals) or other groups can help. Don’t just try to wing it – people’s lives and happiness are on the line