Here is another idea if you do go to munich try Garmisch
I have been there in the summer and its quite big and I would imagine enough skiing for a couple of days.
I have skiied Engleberg and its nice but nothing special.(and its very small) It has a glacier so its a safe bet if you are going in the spring.
Here's the link for weloveto ski. Their reviews are very comprehensive. I think they are the people that used to do the Audi ski guide
I would agree on chamonix that its a bit messy but if you just go to one place and dont try and ski the whole valley its fine.
Zermatt is epic and very beautiful but not cheap Its more like something you'd do for a wedding anniversary and Im guessing as it's his 40th he just wants to ski all day and then have a rake of swallies in the afternoon-an expensive occupation in Zermatt.
(come to think of it as its his 40th you could always let him away for a week with a gang of lads........)
And on that note it will bow out before things start to get thrown!