Last week we laid tile in the family room. On Wed night we grouted. It is now Sat morning and there are still parts that don't look completely dry. They are discolored. Slightly darker than the rest of the grout lines. I'm not sure what happened or how to fix. Friday night at the 48 hour dry mark I tried to use this haze tile and grout cleaner I bought at Lowes. It did not seem to help much. Although I do think it worked a little or I am just getting confused looking at these lines too long. ha ha. Any thougths?

Here is a link that might be useful: