That highlights the main issue I have -- if we're going to reintroduce an animal, we need to understand the current environment. As much as I'd love to have things the way they were 300 years ago, including shipping all you back to Europe, it's just not possible. So, we've got to work with what we've got, or modify what we've got so things work better. Problem is, you hit all kinds of resistance when you try the latter, or you take a chance at screwing things up beyond repair.
I don't know how elk will fit into the current environment -- but I know there aren't any predators. So, I wonder if their population will sky rocket unchecked. Things are drastically different than when they last lived here, so reintroduction based solely on the fact they used to be here isn't enough. Nature will find a balance over time, but it may not be to our liking. And, it make take longer than we short-sighted humans can comprehend.
I also don't know how quail, bear, mountain lion or other natives will fit into a new order.