it doesn't work for anyone right now.
but if they restore it, i dont see why psa employees wouldn't be able to use it. It works well for checking status/loads on express flights, but when you start checking mainline flights it would get a bit wonky. i think the two class cabin may have had something to do with that.
anyway, it was an awesome tool and anyone that used it should submit feedback to them via the feedback form now posted on that site. Hopefully we can get it back, this secureflight BS is not making anyone more secure.