The bit that you've snipped out of the original sentence does make sense.
Because the object has been changed from " a few of them" to the latter "them".
The original sentence did not make sense:
In the words of English for Dummies, The "I" is the subject, the verb is "stepped in", and the object, the ones receiving the action of being "stepped in" is "a few of them".
Strip out all the superfluous words, and you're left with "a few of them I stepped in", If the "them" was referring to puddles, or cowpats, it would be fine. But referring to "people like this", it's nonsense.