Here's the backstory ... Reggie RIPPED the school on Instagram yesterday -- claiming a former male college basketball player was honored with his own banner while Cheryl had to share a banner with 4 other women.
"You guys should be EMBARRASSED and ASHAMED," Reggie wrote ... "Cheryl DESERVES her own wing at the Galen Center."
FYI -- Cheryl is widely considered the greatest basketball player (male or female) to ever attend USC.
But a rep for SC tells TMZ Sports ... Miller has the whole situation down wrong.
Turns out, the school customarily singles out past great athletes and TEMPORARILY honors them with a solo banner.