Unfortunately it is not a simple mesh problem. The mesh is fully intact. I tripple checked that. No duplicate vertices, no stray vertices, no nothing obviously wrong with the mesh. Since i am the second user who reports this issue here, i believe that something is broken either in the distribution of the Dynamic Tee item or it is simply a compatibility issue with Studio-4.5 and/or the Genesis character.
The most puzzling point is that although the item is declared as compatible to Genesis, it provides material sets only Victoria 4, but neither for v5 nor for genesis. Maybe that is the true cause of the problem.
btw a re-download does not help either. And i have already reported the issue to daz people 2 days ago and patiently wait for the answer