sorry van, wasn't ignoing you, just been a bit busy! A few years ago this a consideration but it seems far less so in practice these days.
First, in the UK, many VORs have a co-located NDB mainly to provide back-up if the VOR is oos or u/s. Even if there's no NDB, if the vor failure is unexpected I'll advise the pilot of the VOR failure and watch the aircraft carry on as normal.
I guess the situation might be a bit different if position reports were needed over the VOR - not because the pilots of modern aircraft will have much trouble doing it but because it sounds daft to say ABC is broken report passing ABC!
If, on the other hand, it's Air Antique I'd be ready to offer more assistance if required.