His button switch on a Marquis may be custom or integrated into a handle, Lawrence.
If you can splice the wire back together so all is back as it was, as Roy suggests, Dick, I'd use Lexel everywhere I could to keep water away from the button's bare wire and contact or solder points, and completely around any bell button housing. The same problem crops up with keyless touch pads; lexeling the escutcheon and pad itself does the trick.
The company says that Lexel is not conductive, so I've used it to seal off outdoor Xmas light and solar lantern circuit boards, switches, etc. You just have to be diligent about where you put it and use enough to make a complete seal. Covering a group of wires coming onto or off a board or a switch, that are closely adjacent to one another but on separate solder points, not only is easy but also helps stabilize them and insulate them from one another.
Joel