This game took place in the last round. GM Shulman had 7.5 points. IM Cordova had 7.0 points. A draw would give GM Shulman at least a tie for 1st. A win by Cordova would guarantee him at least a tie for 1st.
After move 18, GM Shulman offered a draw. It is understandable and a smart idea to secure 1st place. The position is somewhat equal and still has plenty of play. Would you take a draw here in this position as White?
I do not allow my children to offer draws. I suggest the same to my students. They must learn to play out positions if they want to improve and get better.
I was in the same position yesterday at the US Open Blitz. I was up by 1/2 point going into the last pair of game against IM Almeida. 1.5 / 2 would guarantee me at least a tie. I went on for the win in both games and scored 2-0 and won the tournament by 2 points.
This is my advice to you, especially young players. Do not let the scores or ratings of your opponents scare you. Learn to control your nerve and try to play out every game. Otherwise, you will limit your own potentials.