At the time, they weren't yet facing a financial crisis. What triggered their financial crisis was the decline in housing prices, and as of September 11, 2003, the housing market peak was still about three years in the future.
In fact, most traders agreed with Frank's assessment, at the time, since Fannie and Freddie stock continued to rise. About half a year after Frank's statement, Fannie stock was worth approximately 20% more than it was the day Frank said it wasn't facing any kind of financial crisis. That's a bull run. As late as mid October 2007 (four years and one month after Frank's statement), Fannie's stock value was STILL worth more than it was when Frank spoke.
Now, this all comes down to what standard we want to hold Barney Frank to. We can fault Frank for his lack of foresight, so long as we're willing to hold him to a standard where he's penalized for failing to recognize a financial problem more than four years before it became clear to the market as a whole, and about three years before the events that would precipitate the crisis happened. However, since I don't believe Barney Frank is a demigod, I won't indulge in judging him according to the standards of one. How about you?