TikZ: Pfad überbrücken klappt nicht

\documentclass{article}
\usepackage{tikz}
\usetikzlibrary{positioning,arrows.meta,calc}

\colorlet{lcfree}{green}
\colorlet{lcnorm}{blue}
\colorlet{lccong}{red}

% globale Settings
\tikzset{
    base/.style={draw, on grid, align=center, minimum height=4ex},
    proc/.style={base, rectangle, text width=10em},
    var/.style={base, circle, text width=4ex},
    %% Stil für Hilfskoordinaten
    coord/.style={coordinate, on grid, node distance=6mm and 20mm},
    % Stile für Verbindungslinien
    norm/.style={->, draw, lcnorm},
    free/.style={->, draw, lcfree},
    cong/.style={->, draw, lccong},
    % Stil für Kreuzungen von Pfaden
    jump/.style args={(#1) to (#2) over (#3) by #4}{
        insert path={
            let \p1=($(#1)-(#3)$), \n1={veclen(\x1,\y1)}, 
            \n2={atan2(\y1,\x1)}, \n3={abs(#4)}, \n4={#4>0 ?180:-180}  in 
            (#1) -- ($(#1)!\n1-\n3!(#3)$) 
            arc (\n2:\n2+\n4:\n3) -- (#2)
        }
     }
    }

\begin{document}
\begin{tikzpicture}[%
    >={Triangle[angle=60:5pt]},% Form der Pfeilspitzen
    node distance=20mm and 30mm, % Vorgaben für Abstände zwischen Nodes in dieser Zeichnung
    every join/.style={norm},   % Default linetype for connecting boxes
    ]

\begin{scope}[nodes=var]
    \node (0) {0};
    \node [right=of 0] (a) {a};
    \node [right=of a] (b) {b};
    \node [right=of b] (c) {c};

    \node [below=of a] (d) {d};
    \node [below=of b] (e) {e};
\end{scope}

\begin{scope}[nodes=coord]
\node [below=of e] (hilf) {};% Hilfskoordinate für definierten Zusatzabstand
\node (hilfps) at (hilf-|c){};
\node [below=of hilfps] (hilfps2) {};
\end{scope}

\begin{scope}[nodes=proc]
    \node [below=of hilf] (f) {f};
    \node [below=of f] (g) {ggg};
    \node (h) at (0|-g) {hhh};
\end{scope}

\node [coord, right=12mm of h.north] (hilfps3){};
\node [coord] (hilfps4)  at (hilfps2-|hilfps3){};

% farbiges Markieren der Hilfspunkte
\foreach \coord/\color in {hilf/green,hilfps/orange,hilfps2/black,hilfps3/blue,hilfps4/violet}
    \node[\color]at(\coord){x};

\begin{scope}[every path/.append style=free]
    \foreach \start/\end in 
        {a/d,b/e,e/f,0/h,f/g,h/g}
        \path(\start)--(\end);
    \path (c)|-(f);
    \path (d)|-(f);
    \path (hilfps2)-|(hilfps3);
    %über Kreuz
    \path (a) -- coordinate(bd-ae) (e);
    \path [jump=(b) to (d) over (bd-ae) by 6pt];
        \path (e) -- coordinate(hilfps2hilfps4-ef) (f);
        \path [jump=(hilfps2) to (hilfps4) over (hilfps2hilfps4-ef) by 6pt];
\end{scope}
\end{tikzpicture}
\end{document}