No you are not over-reacting. If they got wet and never totally dried out you could have mold problems. When my basement flooded, my adjuster told me if problems showed up later (i.e. premature rusting in the washer/dryer) I could reopen my claim. Of course your insurance may vary.
For reference, there were two industrial dehumidifiers plus fans going in the basement for a week, all the laminate flooring in the main area plus the tile floor in the laundry room was removed. The crew had a moisture sensor for the drywall, and removed either a few inches (where barely wet) or 24" (standard for more than a few inches of damp). When the basement RH matched the main floor RH the basement was considered dry, and they then sprayed a fungicide/bactericide in all the wall cavities.
