Issuing talaaq in exchange of the money agreed upon

Q: My question is regarding khula. The wife demanded for separation from her husband and husband was not ready. Finally he agreed for separation (divorce) with a condition of their son's custody and return of mahr and other financial settlement. The entire process was done in India by a lawyer on a legal paper and husband pronounced talaaq three times at one go (please note he had issued one talaq already few years ago) and they got separated. Now my question is, is this considered as second talaaq or khula? Also please be informed that they lived together 2 months after this procedure. So if this is khula that took place, is it right on them to live together? Are they sinning? Request you to kindly respond at the earliest so that I can stop them from sinning further or help them in the best possible way pleasing Allah.

Not living with the new husband out of fear of losing custody of one's children

Q: I have a Muslim co-worker that got married a few months. She was a divorcee. The man she married has a teenage son from a previous marriage. She herself has 2 pre-teens. One being a girl. She does not live with this man as she's scared her ex-husband (whose been married for over 6 yrs now) will gain custody of the children. How valid is that marriage? The new husband is building a house so that her daughter can have her own room and bathroom in the house. By the time the house is built the girl will be 12 and the new husband's son will be 14. Is that allowed in Islam?

Is taking the following oath to become a US citizen kufr?

Q: I have emigrated from an Arab Muslim country to US and lived there for almost 20 years. I became a US citizens and gave up my original arab muslim country citizenship even though I can keep both citizenship in both countries. My original arab muslim country ruled by islamic law but there is a lot of corruption and in America we have freedom of religion and we have mosques. I love America, and have my home there, and my understanding that a Muslim should love the land he lives in and be a good role model citizen and respect the law as long as he is not asked to do anything prohibited in Islam. I wrote and said the following oath upon taking US citizenship:" I hereby declare, on oath, that I absolutely and entirely renounce and abjure all allegiance and fidelity to any foreign prince, potentate, state, or sovereignty of whom or which I have heretofore been a subject or citizen; that I will support and defend the Constitution and laws of the United States of America against all enemies, foreign and domestic; that I will bear true faith and allegiance to the same; that I will bear arms on behalf of the United States when required by the law; that I will perform noncombatant service in the Armed Forces of the United States when required by the law; that I will perform work of national importance under civilian direction when required by the law; and that I take this obligation freely without any mental reservation or purpose of evasion; so help me God." One day I was searching something on the net and read something that was concerning, which was a fatwa by someone (I think from Salafi school of thought) answering someone who asked about the US citizenship oath and the sheikh said that such oath is an absolute allegiance (Wiliya Mutlaga) and hence is considered Kufur! I love my religion Islam. I also love The United States and alhamduliallah feel happy there. Did I commit any apostasy (kufr) by saying and writing the above oath? Am I still a Muslim! Please advise me.

Hadith related questions

Q:

1. Can you give me a dua for protection from hypocrisy (nifaq) and disbelief (kufr). I found the dua for them myself but I don't know if they are genuine or not.

2. Ss this dua genuine "Allaahumma inni as’aluka al-Firdaws al-A‘la min al-Jannah"?

3. I red hadith that out of 100 only 1 will enter Jannah and rest 99 will enter hellfire, does this means most or vast majority of people will have no chance of entering Jannah?

4. If someone tried to seduce some people using techniques but now he realised he made mistake, what does he needs to do to get his sin forgiven?