Maybe I'm an optimist, but I don't believe dogs do things like this out of anger or spite. As you wrote, he knows it isn't right.
What is your pad setup? What are the surroundings? Is it possible that he feels safer pooping under the table when you aren't there? Or maybe he thinks he is hiding the poop under the table since normally he does it outside?
My older boy cannot stand having poop on the pad that is not taken care of right away. It's very upsetting to him.
My other boy was a shy pooper when he was younger. He also had the urge to go, slightly nervous poop, if we left him alone. Could be that your boy, although chill and well-adjusted, knows the weekend is over and just gets a little anxious about time alone and has the urge to go but doesn't want it on the pad.
I agree with Canana's suggestion about blocking access to under the table for awhile. Make sure the scent of the accidents is thoroughly removed from the area too.
Good luck!
__________________ Kristin, Max and Teddy  |