Okay, I have in front of me the book 'Who is who in the Mahabharata' by Subash Mazumdar, so I can fill in some of the things we discussed in the last few pages.
Jalandhara - Younger sister of Duryodhan's wife Bhanumati. She was devoted to Bhima and used to call him King Vrikodara. She once acted as an intermediary to arrange a meeting b/w Bhanumati & Krishna.
Meghasandhi - son of Jarasandha's son Sahadeva. During preparations for king Yudhisthir's ashwamedha yagna, he challenged Arjuna who was following the royal forse. In a short battle that ensued, Meghasandhi was defeated and he then agreed to atend Yudhisthir's yagna thus acknowledging the latter's superiority
As for the Yadavas during the Ashwamedha yagna, both Ugrasena & Vasudev prevented the Yadavas from capturing the horse
When the beautiful sacrificial horse of the Kuru
king reached Dwaravati, the Yadava youths, used force against that
foremost of steeds. King Ugrasena, however, soon went out and forbade
those youths from doing what they meditated. Then the ruler of the
Vrishnis and the Andhakas, issuing out of his palace, with Vasudeva,
the maternal uncle of Arjuna, in his company, cheerfully met the Kuru
hero and received him with due rites. The two elderly chiefs honoured
Arjuna duly. Obtaining their permission, the Kuru prince then proceeded
to where the horse he followed, led him.
On the vanvas question, you are right that Draupadi didn't feel the need to raise her children during her husbands' exile. However, she was the exception, and I wasn't asking why the other wives didn't stay w/ the Pandavas. In the Mahabharata, Dhrishtadyumna was reported as having taken her sons to Panchala, but in the book I cited, Rukmini was said to have helped Subhadra raise Abhimanyu and
My question, though was about the end, when the Pandavas retired. In the case of Krishna, some of his widows self-immolated, while some others retired to the Himalayas to do tapasya. In the case of the Pandava wives, they could have, like Draupadi, left w/ their husbands, who were on the journey to swargalok: yeah, they too would probably have died along the way, but wouldn't they have wanted to accompany their husbands? Chitrangada returned to Manipur to live w/ Babruvahana, which certainly made more sense than living w/ Parikshit, while Uloopi went underwater - it's unclear whether she ended her life, or returned to her original watery kingdom in Nagaland.
Nirmitra or Suhotra or Yaudheya - there is no record of them after the war, which suggests that they died during the war. Had they lived, the least that would have happened would have been that the Pandavas would have made them ministers or guardians of Parikshit when they retired, instead of leaving him to Yuyutsu. All evidence suggests that except for Babruvahana, there were no living sons of the Pandavas.