Joe Rohde is not responsible for the yeti breaking or for it not being fixed. Don't know why some people can't understand that. The company isn't headed by the imagineers.
Of course there are tigers in Asia. But the legend of the yeti lurking in the Himalayas has been passed down over thousands of years. Nobody ever believed or cared about a tiger up there. Replacing the yeti with one would turn a very accurate ride into cultural blasphemy.
It wouldn't biologically make sense either, considering that a tiger could never rip apart a railroad track like that, if it even had the brainpower to react in such a way.
All in all, a terrible idea for which you should be ashamed of posting.

I too would like a ride that revolves around tiger(s), but that ride is not Expedition Everest.