This question was asked in threads that are couple of years old, sorry if this was answered recently.

If i make a reservation with my account, add 2nd person on the reservation, and they check in first, and I never do. Do I still get the point/stay for my account? And would they be able to enjoy the elite benefits without me present?

Many people have reported that this works, but it is against the T&Cs, which require you be staying in one of the rooms in your reservation to get the points and perks. Recently someone started a thread stating he was surprised that his account was shut down for this. IMO it is not worth it to put your points and account at risk doing this.

Why not call the hotel and ask directly if this is acceptable? If they say yes, then you will not have to worry about getting caught doing something wrong. If you are unable to tell the hotel what you are doing than you pretty much have your answer on why you shouldn't do it.

Finally, recently I made a telephone reservation on my account for my sister and her family. We had been making other travel plans, it was late and this was the last reservation so she dropped off the phone. There was a note on the reservation indicating I would not be there. I did not have her cc or passport information which were required but was going to call back the next day with her to add the information. The hotel reached out within hours letting me know they needed her information which I explained they would get. Even though my sister is not Gold or Plat the hotel offered, without my asking, to grant them lounge access anyway. so honesty turned out to work well.

Yes, this has been asked and answered many times before. No, you are not entitled credit for the stay. However, not every property follows the rules and you MAY get credit. Keep in mind that this may be caught at some future date and reversed. If you depend upon that credit to make status, you could lose the credit and therefore lose status, and you may not have time to make it up. Only you can determine your risk tolerance.

Pretty much all anyone needs to know. Since it's against the rules, it's an ethical decision.