A nozzle segment assembly for a gas turbine engine may generally include inner and outer ring support segments and a nozzle fairing positioned between the inner and outer ring support segments. The nozzle fairing may be formed from a ceramic matrix composite (CMC) material and may include both an outer endwall and an inner endwall. In addition, the nozzle fairing may include a strut vane extending between the inner and outer endwalls. The nozzle segment assembly may also include a metallic strut extending through the strut vane between the outer and inner ring supports and at least one secondary vane configured to be received through at least one of the outer endwall or the inner endwall of the nozzle fairing such that the at least one secondary vane extends between the inner and outer endwalls at a location adjacent to the strut vane.