What to do if my sump is bone-dry?
I would second the comments recommending a second opinion.  A sump is in the basement to allow water to be drained away if it accumulates around the footings.  If there's no water there it quite probably means that your water table is low enough that there's not seepage.  It also would indicate that you have decent drainage around the house and rain water is running away and not down along the foundation walls.

Even if there is a blockage in your sump I would expect there to be some water in the bottom if you currently have a water problem.  Blockages often involve crushed weeping tile or other drainage pipes.  However, it would not usually be a complete blockage and if you have a have water on the outside trying to get in at least some of it should be seeping into your sump even through damaged draining lines.