According to my Enthusiasts Guide to the Pontiac Fiero, only four colors were offered. Light Gray Metallic, White, Black, and Red.
Medium Blue Metallic was "offered" in '84, but none were built.
Bright Blue Metallic was an option in '87.
In 1985 the Fiero Precision Driving team had at least one blue Fiero.
So to answer your question. Nope, don't know anything about a factory blue '85 unless it was for the driving team.