There may be a problem in Colony 4. There is no pollen on the base board and there are Wasps which are not being challenged at the entrance. This suggests that supersedure or swarming may have left them without a Queen. There is evidence that mature brood is still hatching out.
The Wasps are becoming more persistent. I saw at least half a dozen around the hives at dawn. If they get access to the hives then they'll rob until there are no stores left.
There might be other reasons why there isn't any dropped pollen. They might not be finding flowers (although other hives have pollen on their base boards). They might be really careful.
I think that more investigation is needed.