This thread is wack. Rupp isn't entering a 10k to run 28+ minutes.
Will he DNS? Maybe! But if he starts, expect the Oly standard or better. He's not that old. His 2:09 at the trials was on a hilly course on a windy day, and he only did enough to win. He ran close to 60 flat on a bike path in a "race" with no stakes.
If he wants to keep the 10k in his back pocket, he will run the standard at this race. If there was a 10,000 meter race for Americans with a $1MM prize in three months, I'd put my money on Rupp winning it.