Even with DG training, you can NEVER trust the "she'll be right" bastards consigning the nasties who do not want to go down the road of costly compliance.
Hmmm - ground cargo type person since 1969.
The best way to be safe is to accept DG. I know it sounds counter-intuitive but if you accept DG what you do is to catch 99.9999% of the DG officially, and handle it correctly.
As soon as you institute a "no DG" policy THEN the bastards REALLY mess you up.
And well-trained cargo humpers get a 2nd sense about stuff... sometimes you just "know" that something is not kosher.
Amazingly, the warehouseman is your friend. If you ever have the time get your fiendly local cargo manager to give you a tour of your cargo handling facility & talk to us slightly grubby people. You have to be able to stomach some pretty vile tea or coffee though