nodal-graph in table spacing issue

nodal-graph in table spacing issue

Good day, hi, I am having some difficulty with including graphics in a
table. If you happen to have some spare time, please kindly enlighten me
on the following problem
I would like to know how to allow the table to align properly, i.e., the
second column is equally spaced and I would like to use multirow on the
the third column but failed. Could you please provide advice or guidance
on the issue? Thanks a million in advance.
\documentclass{article}
\usepackage[english]{babel}
\usepackage{tikz}
\usepackage{multirow}
\begin{document}
\begin{tabular}{ |l|l|l|l| }
\hline
\multicolumn{4}{ |c| }{Convergence} \\
\hline
Time & \multicolumn{2}{ |c| }{Information} & Graph \\ \hline
\multirow{3}{*}{1} & Vertice & 1 & \begin{tikzpicture}
[scale=.3,auto=left]
\node (n1) at (10.6,4.9) [draw, circle,fill=green!20] {1};
\node (n2) at (4,0.8) [draw, circle,fill=blue!20] {2};
\node (n3) at (3.8,11.4) [draw, circle,fill=green!20] {3};
\node (n4) at (0.1,6.4) [draw, circle,fill=green!20] {4};
\node (n5) at (3.6,3.4) [draw, circle,fill=blue!20] {5};
\node (n6) at (7.4,2.3) [draw, circle,fill=blue!20] {6};
\node (n7) at (9,10.4) [draw, circle,fill=green!20] {7};
\node (n8) at (18,10.8) [draw, circle,fill=green!20] {8};
\foreach \from/\to in {n6/n2,n2/n5,n5/n6}
\draw[blue] (\from) -- (\to);
\foreach \from/\to in {n1/n8,n8/n7,n7/n1,n3/n7,n4/n3}
\draw[green] (\from) -- (\to);
\foreach \from/\to in {n6/n1,n5/n4,n2/n4,n1/n5}
\draw[red] (\from) -- (\to);
\end{tikzpicture} \\ \cline{2-1} \cline{3-1}& ${P(1)}$ & 0.5 & \\
\cline{2-2} \cline{3-2} & Chance & 0.5 & \\
\hline
\multirow{3}{*}{1} & Vertice & 1 & 0.5 \\
& ${P(1)}$ & 0.5 & 0.5 \\
& Chance & 0.5 & 0.5 \\
\hline
\end{tabular}
\end{document}