We recently had our bathroom shower redone and are noticing that the grout On the floor does not dry out. It takes over a week for the grout to dry. We have sealed the floor several times. Is it possible that the grout is defective or is it a drainage problem? Are weep holes around the drain industry standard or is it acceptable to install a shower with no weep holes around the drain?

If weep holes were not used around the drain and they need to be, what does the contractor need to do, remove the tile around the drain and redo that section or does the whole floor need to be redone?

I am amazed that you contractor told you that weep holes were not needed. Where did he think the water they got under the tiles would drain out to?
Ever flange type shower drain has weep holes. What usually happens is that the tile man does not protect them and they fill up with tile grout and block drainage.
The solution would be to call your tile man back and have him taken up the floor, clear the weep holes, and retile the shower floor. Good luck, Tom

I'd sue him and hire another contractor.