I have played with the Champagne gene and never gotten a rat with red eyes. They always were pink eyed. HOWEVER - there is such thing as a dark eyed champagne.
Dark-eyed Champagne aa B-C-D-G-mm P-rr
It may be that this rat is a very light beige or a poor eyed champagne. Rats can have many different shades of eyes. The only way to tell would be to take apart it's lineage.