The Cervelo-Bigla rider explained to CBCSports she learned of her exclusion on June 14 via email and made her appeal one week later.
"When I got the news I was in shock, I was in shock, totally shocked," she said to CBCSports.
Karol-Ann Canuel (Boels Dolmans), Leah Kirchmann (Liv-Plantur) and national time trial champion Tara Whitten (The Cyclery-Opus) are the three Canadian riders named for the women's road race on August 7.
The 28-year-old is yet to record a top-ten in Europe but in her last four races she has finished second, fifth, third and second. Those results include two medal in the Canadian national championships with bronze in the defence of her road race title on Saturday.
"I think Canada should just send the best team and if you look at the best team you got to look at results, it all comes down to results," said the 12th place finisher from London. "We have so many races on the UCI calendar it's crazy. I've been racing so much the last two years. After that you look at the results and you pick the best ones from the results, that's it, it should be simple like that."
Numainville, the 2015 Canadian national road race champion, is set to have her appeal heard on July 11.