Hands upside down, I don´t know for sure what they meant, but someone with hands upside down could be quick to ask (but not to work in this case).
There are also people that stand upside down on their hands (a headstand) in yoga, for example, in such moment one can´t work or do anything, of course!
Not to mention that a turtle with its hand upside down, can´t work, eat, unturn, or do anything either.
Just rumblings of mine here, just for guessing and joke´s sake. Now a native insight would do wonders to our learning and English! he he.
Although, in this case, it could really be some euphemist for "being lazy", who knows?