I'd want the safety switch wired to shut off the dehumidifier if that pump fails. I had those pumps for 30 years in my old house for the A/C, and several failed over the years. Without the switch to shutoff the A/C, I'd have had quite a flood in the basement. You'd be surprised how much water a decent dehumidifier or A/C unit can pump out in the summer months. That's especially true if you don't go into the basement area where the pump is.
At my new house, the dehumidifiers and the A/C all drain into the drainage channel around the basement edge and my sump pump and backup pump can deal with them. Yes, the sump has an alarm if there's high water in the case of multiple failures, it goes through my security system so I get an alert anywhere I am. I've seen too many flooded basements to want that here!
