The Nephites had been unable to raise an army due to the rapidity of the attack, and the unexpected location of the attack. However, they did find out about the attack fairly quickly, and desired some type of retaliation. It is not surprising that they would want to gain the return of the prisoners, not simply because they were Nephites, but because of the nature of prisoners in the Maya territories at this time. The fate of these prisoners was likely torture and sacrifice, as well as political currency and prestige. The recovery of those people would deny the Lamanites much of the glory of their attack.
We also begin to see in this verse the military function of the religious leader of the Nephites. Certainly we have Moses as an Old Testament model for a priest with duties during war, but we have a slightly different role here that may be related to the interpreters that are part of the royal possessions. We are not told that Alma consulted the interpreters, but they were apparently available for such use as Alma requires to answer this request:
Mosiah 8:17
17 But a seer [one who has the interpreters] can know of things which are past, and also of things which are to come, and by them shall all things be revealed, or, rather, shall secret things be made manifest, and hidden things shall come to light, and things which are not known shall be made known by them, and also things shall be made known by them which otherwise could not be known.
We are specifically told that Alma the Younger received them upon his elevation to the seat of the high priest and chief judge (Mosiah 28:20). While they were clearly part of the emblems of royalty, it is possible if not probable that Alma retained them as part of the responsibilities of the chief priest, since they worked only for those commanded of the Lord to use them (Alma 8:13).
Cultural: Zoram is most certainly named after the servant who traveled with the original party. While he was a servant in Jerusalem, he was clearly considered a respectable member of the Lehite community. The preservation of his name indicates that it was associated with good memories and histories. We find no Nephites with the names of Laman or Lemuel.