Dynamic generally means any type in Haxe. However, it does not mean Void.
You cannot assign func a function that has a void parameter list. It DOES require a parameter, but that parameter can be of any type.
It may seem kinda obvious, but I was tripped up on it because I thought Dynamic could represent any type of value, including a Void parameter list. Which, in hindsight, seems kind of ridiculous, but none-the-less, it happened.