Go into the hive and check for SHB. If nothing looks amiss, it is Goldenrod honey being processed, and the larva are drones being kicked out for the winter.
If it is SHB, you need to take immediate action.
that could be several things. Are the larvae being carried out by bees or are they crawling around, or just sitting there.
The soured smell could be goldenrod honey being cured. The larvae could be wax moth. (best case)
The soured smell could be slimed SHB frames. (middle of road case)
The soured smell could be Foul Brood and the hive would need to be burned. (worst case)