I would also check the seals on your humis. If they have a light inside that will work. If not you can use a flash light. Turn off all the lights in the room make it as dark as possible. Either turn on the light or place a flashlight inside. Check to see if you can see any light coming through the seals.
I would also double check your gauges. I would just take all of them and put them in a Tupperware with a secure lid and drop a 60gram boveda in there and see if they regulate in a couple hours. If they don’t regulate I would recalibrate the affected ones. His is more just a CYA move. When were they calibrated last?