What is the meaning of "Chanunu Osam"?
Rashi: We had mercy on them [for they had no other solution].
Radak #1: It is as if says Chanunu Mehem (Tanichu Lahem - leave them).
Radak #2: This is like "Asher Chanan Elokim Es Avdecha" (Bereishis 33:5), i.e. give them to us for a gift. 1
Malbim: This is said incredulously. Is this Chaninah 2 , that we do not make war to take back their wives from them?
What is the meaning of "Lo Lakachnu Ish Ishto ba'Milchamah"?
Rashi: We took, in the war with Yavesh Gil'ad, wives for only 400 men of them.
Radak: We did not 1 take for the remaining Bnei Binyamin wives in the war - we killed them all!
This is based on an old text of Radak. (PF)
Why did they say "Lo Atem Nesatem..."?
Rashi: If you are worried about the Shevu'ah, you are not culpable, for you did not give [your daughters].