It is mentioned in Valmiki Ramayana, Sundara Kanda, Sarga 10 that Lord Hanumana seen many women there in the palace of Ravana but when he saw Mandodari, because of her beauty and appearance he thought that she could be mother Sita.
taasaam eka anta vinyaste shayaanaam shayane shubhe |
dadarsha ruupa sampannaam aparaam sa kapiH striyam || 5-10-50
Yes, they did according to Adhyātma Rāmāyaṇa:
Having thus deliberated in council with his ministers, Rāvaṇa went out to fight Rāma with the remnant of his Rākṣasas, like a moth
rushing together with other moths into a blazing fire.
2–3. All those Rākṣasas were killed by Rāma in battle with sharp
Probably she married Vibhishan:
After the death of Ravana, Rama advises Vibhishana to take Mandodari
as his wife, even though he already has a wife. A theory suggests that
Ravana's race may have had matrilineal families and thus, to restore
order in the kingdom after Ravana's death, it was necessary for
Vibhishana to marry the reigning queen to get the ...
According to the Puranic Encyclopedia, the Uttara Rāmāyana narrates the story of how an apsara named Madhurā turned into a frog and then into Mandodari who becomes the adopted daughter of Mayasura and his apsara-wife Hema:
Maya, an asura, was born to Kasyapaprajāpati of his wife Danu. Once Maya went to Devaloka to see the dances of the celestial maidens ...