Can I see the table?
This has shown to be hard for me to explain in words. sorry.
Often, if the wood just got wet irregularly,
namely the top had a varnish and the bottom didn't and it was in a damp garage sucking up water from one side. ...........
Or one time a roof leaked a little onto a paper cutter's board........
One side wet and the other dry??
Sometimes all you really have to do is equalize the water. In the case of the paper cutter board I just set it against the wall with the humped side facing the woodstove a few feet away.
It took about a week but it came back smooth as 20 year old Bourbon.
With all warps and cups in wood, you have a concave side and a convex side. The wood is wetter and has swelled on the concave side, and is drier on the convex and shrank.
There have been times all I had to do was flop a plank of wood onto grass damp with morning dew, in the sun.
Put the concave (dish) side down so it can suck up a little water and the sun will dry out the convex (hump) side.
yours Scott