To answer your second question tofu does have to be refrigerated but has a decent shelf life.

Close but they're a little different! Aquafaba is whipped juice from chickpeas, that's a great vegan substitute for like a meringue. Silken tofu is super wet soybean curd, you can get it in Asian markets if you haven't seen it before. I think that functions a little better as a binder for a dense product like this or pound cake.