On a positive note, they have given me ANOTHER reason NOT to spend money!
The issue that was raised in this thread was players not receiving the coin reward for the trade. I've done a 4 day trade and tested to make sure that the 20,000 coins not only dropped but were not removed. They stayed.
The 2 minutes timer was clearly accidental and was updated to the original specs. Feedback has resulted in the team making another change to a smaller 4 day timer. I can see that the timer in the 2nd building (cave of courage) also has a 4 day timer but I'm not up to that goal yet. Given this issue has been resolved, I'm going to close this thread. Feedback about the timer should be made in the correct forum, ie Suggestion & Feedback.