It's not military SAR any more but most of the crews are ex-mil.
Every job is different and you use your best judgement and experience to perform the rescue and, if it really is too risky, you don't do it.
But they should have been given the chance to assess it and winch if required rather than landing.
A rooftop in the dark is no more tricky than a mountainside in the dark or a fishing boat being tossed around in 30' waves.
I have put a winchman into a building through a window before and it isn't that difficult - at least the building stays still.
Have a look on jetblast - there is a link to a hotel fire in Las Vegas many years ago where military helicopters winched from balconies on the burning building - they saved many lives.