I see no reason why Harry Giles should even come out this year.
It's a loaded draft and his stock is at an all-time low. Take the year to rehab and dominate college basketball next year.
TP.
With all the anticipation and hype of Giles even just playing a game, I think that even the possibility of what you suggest has been lost and so hasn't been considered by many.
In support of your argument, assuming that he works his way back to playing health, that would be a prudent decision, both health-wise and draft stock-wise.
The flip side is that if he doesn't come out and gets re-injured, he's done. Look at Noel and Embiid. Injured, but still got taken in the lottery. Some team will take a chance on Giles this year, especially if he falls to later lottery. That's guaranteed $$$ for Giles, with the only down-side being that he could've made more, if he stayed and IF he remained healthy.
Also, next year's draft is loaded with bigs.
Tough decision. But I think that the short-term guaranteed $$$ is too much to pass up.