How is that very safe? Presumably were looking at this unreviewed web app instead of what they were looking at before.
Can the naysayers be sued by the family of some kid who died because dispatchers weren't allowed to evaluate a new tool because change scares some people? (No, of course not. And that's why there are so many bikeshedders.)
Certainly change would be bad if the programmer in question blidnly modified existing systems. But I don't see any of the reactionaries asking that - they just assume the worst and go off on how unsafe it might have been.
But a new webapp bundling data from other systems into a new view? It shouldn't be any problem at all. The professionals on the phones are the very ones who would have to evaluate the information it returned so there's no way around letting them use it.