Wrong......again. The crux of their argument is that the stones used to build the Sphinx Temple came from the same quarry surrounding the Sphinx as is proven by the stratification on the stones.
Let's review the source again
"Dr. Schoch noted that a nearby tomb, also carved out of limestone, was thought to have been built at the same time as the Sphinx. But, he said, his studies clearly show that the Sphinx is so much more weathered than the tomb that it has to be more than 2,000 years older. So if the tomb is dated at 2500 B.C., the Great Sphinx has to be dated no later than 5000 B.C., he said.
What you said is completely irrelevant to the fact that the limestone temple next to the limestone Sphinx was built
during dynastic times, and the Sphinx was built during a time
prior to the Saharan wet phase. The evidence of that fact is that the temple is not weathered by water, because it does not go back to the wet period like the Sphinx does. It's very simple to understand. Oh, and you still haven't provided a source for your claim that somehow the Sphinx's limestone is "more porous" than the other limestone surrounding it.