The 114th PA wore both the fez and the turban into combat, either is correct.
Troiani's painting "Barksdale's Charge" depects the 114th wearing both as Barkdale's men slammed into them on July 2nd.
Troiani is too young to have seen the unit live as well, but I'll trust his research on the subject any day of the week and twice on Sunday.
The Roechling painting is among my favorite ACW subjects, the original hangs in the visitors center at Fredericksburg, it's stunning to see it in person...................