The name of the Atharva-Veda -Kanda 5 -Sukta 17 is Brahmajaya sukta. The meaning of word Brahmajaya is wife of guru , or Guru-Patni. Which is also called as Brahmani or consort of Brahmana. Since Bṛihaspati' is Guru of Devas , his wife Tara is considered as Guru-Patni. So the Brahmana women here is "Tara" wife of "Bṛihaspati"
I am here taking the help of the commentary of Atharva-Veda By Shripad Damodar Satwalekar . Which is called Atharva-Veda Subodh Bhashya.
One mantra you quoted in question is -:
सोमो राजा प्रथमो ब्रह्मजायां पुन: प्रायच्छदहरुणीयमान: |
वरुणो मित्र आसिदग्निर्होता हस्ताग्रुह्या निनाय || AV. 5.17.2||
King Soma first of all, without reluctance, made restitution of the
Brāhman's consort. Mitra and Varuna were the inviters: Agni as Hotar
took her hand and led her.
Is this verse related to a specific incident ?
Yes , this mantra is related to specific incident of Tarakamaya war (तारकामय).—This is Devasura (in between gods and demons) battle happened in Krita Yuga.; Tara (Traka , Bṛhaspati's wife) was abducted by Soma (moon) was the reason for war between the God's and the Demons. Shukra joined Soma while Lord Shiva and Indra took up Bṛhaspati's side . The ended with the intervention of Brahmā who gave Tara back to Bṛhaspati. Tara is called here as" BrahmaJaya"
Or Wife of Brahmana guru Bṛihaspati' .
In the above mantra there is description of Soma or moon returning the wife of Brihaspati to him. Soma returned the Brahmana women Tara to Brihaspati. Mitra and Varuna was present at the time and Agni(fire) was witnessa and Hotar.
Purpose - The purpose of above sukta is protection of Wife of Guru and hence all of the womenkind . This sukta tells us that in a nation
, its people should always respect women. They should be given the
highest respect and freedom and also protection and safety. The
nation and the people of which does so flourish . And those who don't