I am wondering just what you mean by "picked up his pay". Major William DuVal may have signed a receipt for a certain soldier's pay with the intention of delivering it to that person. It does not necessarily mean he "stole" it. He may have been called "Mister" DuVal after the Revolution (although that is very doubtful. Even today military men usually keep their titles after retirement). But Major William DuVal was also the mayor of Richmond, VA, at one time too. I doubt very much that he was either irresponsible or a thief or he would not have held either of those positions. He may have accepted the soldier's pay in view of the fact that the books were about to close and that soldier might not have been able to be there due to sickness, a wound, or some other reason.