As long as the marriage duration has not ended, permanent marriage is not valid. She is still his wife by the temporary marriage. If this marriage expires or he ends it by forgoing the rest of the duration, then they can conduct a permanent marriage with the fulfillment of the rest of the conditions.
All what believers do in order to express their grief and sadness and show their loyalty to the Ahlulbait (peace be upon them) are amongst the best of deeds. One should do so in such a way that the person is not harmed with a prohibited kind of harm.