Uncured live rock means that there are dead/dying/decaying stuff on the rock. Cured live rock means everything that was dead/dying/decaying is now gone, therefore the rock is "cured".
I am not sure what your LFS meant by "it was there for 2 weeks and it's good rock". 2 weeks is not long enough for uncured rock to cure, or they may have cured rock that has been sitting there for 2 weeks. Ask them which one it is: 2 week old uncured rock or 2 week old cured rock. Makes a big difference.
If it's all cured rock, that means the rock has all the beneficial bacteria and the amount of die-off is minimal, just whatever is related to the rocks being placed in an aquarium different from where they came from. This may, indeed, be completed in a week. Keep an eye on your parameters and go slow with adding livestock.