My 80 year old uncle and his wife are going to umra for the first time without a Maulana or group. I had one question. If they complete the umra, finish the taqseer, MUST they do the tawaf un nissa the same day. It might be to taxing for him.

No they don’t have to do it the same day. Once taqseer is done they are out of ihraam and they can come and do it the next day or anytime before they leave Mecca.