Base planet sizes range from 1 to 20, plus size 26. This was clearly a size 26 planet with a +PQ event. +PQ events can improve the PQ by up to 50%. Soil, Habitat, and The Terraformer can each add 10% and terraforming can add 20%, for a maximum legal PQ value of either PQ51 or PQ52, depending on whether that max is actually 50% or 49% from the event.
I'm not sure what the anomaly cutoff is. It -MAY- be possible to reach a PQ50+ planet by legal means and have it render you a zero score (anomalous result). I don't know what the cutoff point is for the game checking PQ's for mods that are "out of bounds". I'm pretty sure Elendil's planet won't set off alarms, though.
As for being good, he could either have captured the planet from an AI, or a single planetary event moves alignment at most by ten points. He could have one or two evil moves and plenty of good ones, and easily qualify as "good".
Nice planet, Elendil!
Humorous portrayal. Perhaps you will satisfy Lee's curiosity and report on the game, to tell us how you came upon this paradise?