Brookfield's Tropic World, which did not begin to open until around 1984, was originally envisioned in the early 1970's as one of the earlier walk-through jungle building concepts, and many believed it would not succeed. A significant number of problems occurred during development, including some rare birds escaping, and it was nicknamed 'Dickinson's Folly' after one of its advocates.
It definitely doesn't predate Topeka or the other examples, but it was envisioned around the same period.
I'm not trying to stake a claim of any kind of 'first', I just always found its long development period an interesting fun fact.