How to set exact spacing in longtable?

I want to make the following table with the text in the most left column is centered (red dotted line) as follows:

My current work is as follows:

documentclass{article}
usepackage{longtable,enumitem}

begin{document}
    centering
    setlength{arrayrulewidth}{0.2mm}
    setlength{tabcolsep}{14pt}
    renewcommand{arraystretch}{1.3}
    begin{longtable}{|p{2.3cm}|p{4.9cm}|p{4.9cm}|}
        hline
        &   textbf{KROHN-RHODES DECOMPOSITION} &   textbf{JORDAN-CHEVALLEY DECOMPOSITION}  
        hline
        endfirsthead
        multicolumn{3}{c}%
        {tablename thetable -- textit{Continued from previous page}} 
        hline
        &   textbf{KROHN-RHODES DECOMPOSITION} &   textbf{JORDAN-CHEVALLEY DECOMPOSITION} 
        hline
        endhead
        hline multicolumn{3}{r}{textit{Continued on next page}} 
        endfoot
        hline
        endlastfoot
        textbf{Purpose} & To decompose the semigroup of EEG signals in terms of affine scaling EEG signal groups, aperiodic semigroups, and the group of diagonal EEG signals. 
        & 
        To express the elementary EEG signals (unipotent and diagonal matrix of EEG signals) as a sum of their semisimple and nilpotent parts. 
        hline
        textbf{Main Results} & Theorem 1, Theorem ref2, and Theorem 3.    
        & 
        Theorem 4 and Theorem 5. 
        hline
        textbf{Interpretation} & begin{itemize}[leftmargin=+.1in]
            item The EEG signals can be described in terms of simple algebraic structures.
            item The building blocks of EEG signals can be perceived as prime numbers.
        end{itemize}   
        & 
        begin{itemize}[leftmargin=+.1in]
            item The elementary EEG signals can be written as a sum of their simpler parts, which is similar to prime numbers where some primes can be written as a sum of two primes.
            item The results provide a substantial manifestation that the EEG signals contain some patterns similar to prime numbers.
        end{itemize} 
        label{}
    end{longtable}
end{document}

that produce:

Please help. Thank you.