Some of the guesstimates here are hilarious. OG had a house in Riedau in Austria for 20 years now. He will go back there after his coaching career, and probably he will live there until he dies. One of the reasons why he switched from Wolfsburg to Frankfurt was because Frankfurt has a nice big airport, so he could fly home more often. London has several nice big airports, so that's a plus. 😆
He's earning a ton of money already, and his need for yachts, jets and penthouse condos is limited. I'm sure he doesn't mind the money, but the thought that he can be manipulated into doing something he doesn't want to by giving him even more money is ridiculous.
As martinelliff pointed out, this is about ambitions. And the ambition isn't to just play in the Champions League, but to win it. Note that he made the Champions League qualification with each of his last three teams (LASK, Wolfsburg, Frankfurt), and those were also the years when he left, so qualification alone can't be all that relevant - the more important question is how much perspective there is beyond that. At the beginning of this season he said Palace is in four competitions, so there are four titles to be won. I'm sure that's what he meant - not that Palace WILL win four titles, but that those goals are not totally out of reach. So there you have his motivation.
And Ollie will NOT extend this year - he has no pressure and no other reason to do that. He will see how the team develops, how the football world develops and how his relationship with SP develops, and then he'll make that decision early next year. I also don't expect him to go to ManU if they sack Amorim tomorrow. The simple reason is that he's much more likely to win something with Palace this year than with ManU - and he's also built something emotionally that's not finished yet.
On the flipside, he has little to win by abandoning ship now, and I'm not even sure if he could pull that off because so much of his work is based on personal relationship and preparation. If a big club talks to him early next year and makes a juicy offer for a smooth transition next summer, that would probably tempt him. If it's not ManU, there will be other offers. Then he will compare that to what he has at Selhurst Park, and make up his mind. If the package is right (remember, ambitions isn't just winning the CL ten times, but it's also about making the fans happy) he might stay, but I can't see how counting stacks of money would play any role in that.