Requesting Compensation from United for Flight Delays

In February, my parents flew down to South America to join me for a trip in Rio de Janiero, followed by a week spent in Buenos Aires, the location I call home for at least half the year.

I booked them in United Business between Charleston, SC and Rio de Janiero using United miles, and LATAM Business between Buenos Aires and Miami using American Airlines miles.

United Compensation for a Delayed Flight

A few weeks ago my United flight from Houston to Buenos Aires was delayed 13 hours. United automatically offered me 7,500 miles or $100 United credit as compensation, but I was able to increase that offer to 17,500 miles or $200 credit with a simple email.
The Delay
I was heading from the Chicago Seminars to my winter home in Buenos Aires. I booked the award for 30,000 United miles the week before departure using secret United award space.