What other evidence do you need that the tiger could readily escape its confined area, get all the way over to the cafe, and start slicing and dicing.
Source please.
If it is true this tiger got out of the enclosure before, the zoo is totally responsible.
If it is not true and this is the first time the tiger got out, it is because of the provocation the kids did.
That would weigh heavily on who is at fault here.