Sheridan mentions the following officers in his official report of the Valley Campaign (though with fewer details):
Ltc John Kellog, Chief Commissary, died in 1865
Ltc Cornelius W. Tolles, Chief Quartermaster, killed in October, 1864
Ltc Henry H. Young, Chief Scout
Ltc Joseph O'Keeffe, (don´t know his staff position), back with the cavalry and mortally wounded at Five Forks 1865
Asst. Surg. Emil Ohlenschlager, Medical Inspector, killed in October, 1864
1st Lt John R. Meigs, Chief Engineer, killed on October 3, 1864
He also mentions several officers by rank and name who were temporarily present and sent from Washington, from the Engineer Bureau and from Grant's staff. Maybe I´ll find some more after sleep (04:20 a.m.).