This is just silly. If you're going by the core rules, that's one thing, but the DM has the right to say both "No, this new class from this book does not work with my campaign" and "These two classes from these two different books combine in a way that ruins the fun for other people."
Telling the DM to increase the power level of all his NPCs to match the PC is a shortsighted viewpoint. In order to make a character who will even remotely challenge this PC, the DM will have to make characters who could convince the other PCs to give over all their money without trouble. Add to this the fact that the PC is powerful in an area that the DM cannot use back at the PCs -- social skills, where even if the NPC has a +34 Bluff check and the PC has no ranks in Sense Motive and a Wisdom of 8, the player can say, "Nope, I still decide that I don't want to go along with it, even though I can't sense anything untrustworthy about him" -- and you've got a PC who can change the entire face of the campaign. The only way for NPCs to compete is to smear the PCs names with incredibly powerful Diplomacy checks against other NPCs. Do the other players in the group relish the idea of being outcasts and criminals one week, then heroes again when the PC makes an even bigger Diplomacy check, and then outcasts again the week after that when another NPC smears them, and then heroes again, and so on?
If this character doesn't fit the concept of the DM's game, and the DM believes that it's affecting the group's overall enjoyment level, then the DM is completely right to, at the very least, ask that it be built with the core rules.
Or, on the other hand, the DM could simply have five ogres ambush the character. This PC would, in a single fight, be smooshed, and then that would be the end of that. I'm sure that the PC's player, who is adamant about building someone this focused, will have no trouble accepting the utter weakness of the character in the area of personal defense and combat. That is what people are saying, right? That the DM should just play by the rules, and that if this character is weak in combat areas, the DM shouldn't go easy on the PC just to keep her alive? So if the evil bad guys know that the PC is capable of turning the king's opinion against them, and if their most logical choice is to eliminate the PC, then the PC's player will understand when the assassins come calling?
I actually did this to one of my PCs, a bard who had done enough high-profile public stuff that it became obvious to the campaign bad guys that he was going to be trouble. They lured him out into the woods and tried to kill him. He survived, barely, but was much more careful from then on. It wasn't me, the DM, trying to kill him. It was a natural result of him tweaking the noses of very powerful people.