My initial google search yielded the same result - I can't find a pic of a 772 with mood lighting, and can't quite tell if it even has the bulkhead Polaris blue wall found on the 773. Though I've heard that sometimes on the 773 they don't use the mood lighting so its hard to tell if pics online of the 772 the lighting is off or not installed.
With 14/15 ships now retrofit, I'm surprised no one has commented here with direct experience after flying one or hasn't commented on the lack of a full interior refit?
Maybe that's just me - seems like a missed opportunity for UA