First, let me say that this is not reported speech, where special rules apply when we describe what somebody said or thought. This is simple narration- telling a story.
Note also that the word native as a noun refers to a person who was born in a particular place, not to the place where he or she was born. I have used the word village instead.
In each of the examples, one version is in simple past (he climbed/she went) and the other is past perfect (he had climbed/she had gone). Both versions are grammatically correct, but we usually try to use the simplest tense possible.
We use past perfect to explain the sequence of two events: the event or action described by past perfect takes place before some other event in the past. We only need to use this when there are no other indications of the sequence. In the first example, the use of and clearly describes the sequence (climbed -> fell), so past simple (version b) is satisfactory.
b) He climbed on the electric pole for repair work and from there he fell.
In the second example, the linking word where does not define the sequence: if you look at version a:
a) She went to her village where she was raped by her uncle.
Does this mean that she went back to the village where she had previously been raped by her uncle, or does it mean that she went to the village and after she arrived he raped her?
In this example, then, the use of the more complicated tense, past perfect, is justified. If returning to the village occurred before the rape, version b is correct.
b) She had gone to her village where she was raped by her uncle.
Alternatively, if the sequence is the other way round (the rape was earlier), you could write it as
c) She went to her village where she had been raped by her uncle.