He and some friends were talking together, and one of them said something that referred to, say, a funny line from a TV show he hadn't watched, or a movie he hadn't seen, etc. The other friends burst out laughing, but the reference was lost on him, so he just looked confused and wondered what they were all laughing at.
I have no idea if the German sentence has that meaning or not, but that is where the English sentence gets used.
He didn't see the link between their words and anything, because he had never seen the TV show, so although what they said made everyone else laugh, the joke went right over his head (to use another expression).
Maybe another way of putting it is that the reference was clear to everyone else, but not to him.
It's somewhat idiomatic, especially the English translation they offer (which personally I think is so strange it's wrong...). Fehlen=to be missing or absent; Bezug=reference, link (comes from Beziehung, relationship). It means he doesn't get the reference/see the link. Literally, the link is missing for him.
Surely: "It has no bearing ON him", meaning that it is not relevant to him?
201 fires, nice! In "It has little bearing for him" him would be the indirect object and therefore the dative ihm. It's always difficult to translate "fehlen" because you don't use it exactly the same in german as you do to say something is "missing" in english. Here fehlen is an intransitive verb, and always takes a dative object. I don't like escape in this context because it makes the Bezug seem more active or willful, but yes, that is a correct interpretation of the sentence.