The panel will also consider punishment for anyone found to be involved in graft which saw 482 batteries disappear from a consignment withdrawn from stores in December.
The six staff members involved in the withdrawal were a director, an assistant managing director, two supervisors, a service officer and a mechanic.
The final case report will be filed to Transport Minister Saksayam Chidchob.
The company previously set up an anti-corruption centre to receive complaints from whistle-blowers but none has been reported since October 2019.