I'm just a parnet and cannot speak for the YS program, but I believe that they stick to the minimum requirements as noted on the DYS application FAQ. As far as I know, they do not accept lower scores, even with an exceptional portfolio.
That was my understanding as well. I thought that the portfolio option was for kids who had achievement scores that qualified, for instance, but hadn't been tested on IQ at all due to cost not for kids with scores that didn't qualify otherwise. That's not to say that the OP's child might not qualify if retested on IQ at a later date, though.
