But surely it’s a reasonable assumption that Wenger’s decision to give him games in the CL was influenced by wanting to keep him happy? Otherwise, what do you suppose Wenger meant by the following?

"If they do not play, you can't keep two world-class goalkeepers."

If this is not about keeping both of your goalkeepers happy, then what else is it about? What is to stop him having two world class goalkeepers and only ever playing one of them, if not keeping them both happy?