Like Jim and Ed I doubt that the ruling was right.
However, I do not think you should be so surprised over the pass of 3D. My guess is that opener was not completely certain about the meaning of the double, and re-considered after the 3D bid. Sure, he should have called the Director then himself, but players usually don't.
Still, there was both misinformation and unauthorised information: it seems likely that the non-offenders would have reached 5C some of the time, so should probably have been given that; or if in a Law 12C3 jurisdiction [such as England] given a weighted score including a part of 5C.