Disoriented?
I am suggesting that if they were on Tango taxing for RWY 9 instead of RWY8R it was by request for the said purpose of using the longest Runway. If so, they would not THEN decide to to do an intersection departure.
From the runway diagram, when at T1 you have to turn left and enter the runway, there is nothing straight ahead... OR right , then a Left onto Sierra. If disoriented, T1 could appear like the entrance at "S" and that you have reached the start of Runway9. Disorientation seems to be a factor.