How to make center the author names and put the institute and date in bottom of slide in beamer?

I want to make a slide. I make code as below.

documentclass[xcolor=dvipsnames, 10pt,notheorems]{beamer}
usetheme{Antibes}
usecolortheme[named=Red]{structure}
usepackage[utf8]{inputenc}
usepackage{amssymb}
usepackage{amsfonts}
usepackage{amsmath}
usepackage{xcolor}
usepackage[english]{babel}
newtheorem{definition}{Definisi}
setbeamertemplate{theorems}[numbered]
setbeamertemplate{caption}[numbered]

begin{document}

title[]{TITLE}

author[]{{textbf{by:}
    begin{center}
        begin{enumerate}
            item Author 1
            item Author 2
            item Author 3
        end{enumerate} 
    end{center}
}}
vfill
institute{{DEPARTMENT OF MATHEMATICSABC UNIVERSITYCITY}
    date{}
}

begin{frame}[plain]
    titlepage
end{frame}
end{document}

And the result is

Why the begin{center} ... end{center} and vfill is not working?

I want make title page as this picture.

So, how to make center the author names and put the institute and date in bottom of slide?

begin{enumerate}
        centering
        item Author 1
        item Author 2
        item Author 3
end{enumerate}