I think that this is an interesting question. You actually have done better than most students. I always find it easier to pare down student writing as opposed to adding in. For this particular question, all you have to do is pare down and you are set.
In terms of what you have, you should also be commended for not wanting to end a sentence with a preposition. Students have a tough time grasping this because of the gap between speaking and writing. When we speak, it's easier to end sentences with prepositions. For example, "Whom did you vote for?" is easier to say than "For whom did you vote?" The first one is more accepted as spoken English, while the second one, albeit grammatically correct might sound more foreign to say.
In your particular question, this is where you are. Both sentences place the preposition "for" accurately in terms of going before "whom." Yet, since it's already in the sentence, one does not need it again. The first sentences has it twice, once in front of "whom" and then after respect. Since its placement in front of "whom" has already established its present, it is not needed again. Accordingly, the second sentence is correct because it only uses the preposition once.