It depends on how close you are and how much the model moves. Another option would be to try this:
1. Print a real t-shirt with a grid on it in the graphic area. (maybe the grid could have 10 lines by 8 lines)
2. Shoot the model wearing the t-shirt. No green necessary.
3. In AE, make a comp of 10x8 proportion and apply the grid effect to a comp-sized layer, 10 lines by 8 lines.
4. Drag that comp into the main comp, over the model.
5. Shrink the layer down and apply the mesh warp effect, using 8 columns by 10 rows (or whatever).
6. Keyframe the mesh warp to match the grid on the model's t-shirt.
7. When done, add the new graphic to the comp that contains the grid. It will be distorted to match the t-shirt.
You should shoot a test.
Caveat: I haven't tried this ... I just made it up right now. Or maybe I saw it done somewhere.