It's an option - it may be that some of the people involved are unaware of all the possible ways one can get pregnant, and I feel like those who've signed a chastity pledge are also the ones most likely to not mention any sort of acts they've performed, and instead just deny having had sex (which is possibly technically true).
Yes, it has been documented. Sperm can survive the digestive track:
Yes, it is. If semen got on someone's hand at the wrong time, this could result.
I still don't see how that could lead to pregnancy. Could you please elaborate?
Well, you see, if semen finds its way into the vagina, pregnancy is a very real chance. So, if a woman gets semen on her hand, and then touches her genitals, she could get pregnant.