Stick a fork in us

After three days of not asking, cajoling or otherwise begging our son to go to the bathroom, he did the absolutely unthinkable.

Jim found him in his room at nap time with no Pull Up on and a poop on the floor. Two days ago he put his own poop in the potty. He's completely devolved from a boy who once went to the bathroom independently to a child who poops on the floor.

Rewards do not work.

Punishment does not work.

Frequent, somewhat forced visits to the bathroom do not work.

Clear expectations do not work.

Positive encouragement does not work.

Putting the child back in diapers does not work. (He just tries to take them off after he poops and makes an unholy mess that makes mommy cry.)

Ignoring the issue does not work.

I'm not even sure that naked time would work anymore since pooping on the floor is apparently now an option for him.

We are officially out of ideas.