\addcontentsline{toc}{section}{Titre de la section} ne numérote pas la section

C.   Chapitre 3eme 
C.0. une section
C.0. autre section

\\addtocounter{section}{1}

\documentclass[french,a4paper,twosize]{scrreprt}
\usepackage{minitoc}
\usepackage[french]{babel}      % titres et typo en français
\usepackage[hidelinks]{hyperref}

\begin{document}
\dominitoc
\tableofcontents
\appendix
\chapter{Annexes}
%\minitoc

\section{Etais}

Bla bla

\chapter{Documents techniques}
\minitoc

Autres blablas

\addcontentsline{toc}{section}{\protect\numberline{\thesection}Résultat technique 1 }
\adjustmtc
%\includepdf[pages={1-12}]{documentFinal.pdf}
Blabla.pdf
    \addcontentsline{toc}{section}{\protect\numberline{\thesection}Rapport geotechnique 2}
\adjustmtc
%\includepdf[pages={1-}]{Rapport_G0_.pdf}
Bla-bla.pdf
\chapter{Documents comptables}
\minitoc
\addtocounter{section}{1}
\addcontentsline{toc}{section}{\protect\numberline{\thesection}Devis étayage}
%\includepdf[pages={1-}]{DevisEtayage.pdf}
Bla-bla.pdf

\addtocounter{section}{1}
\addcontentsline{toc}{section}{\protect\numberline{\thesection}Facture étayage}
%\includepdf[pages={1-}]{FactureEtayage.jpg}
Blabla.pdf
\end{document}

Page  Destination                 Name
   1 [ XYZ   89  758 null      ] "Doc-Start"
   1 [ XYZ   89  758 null      ] "chapter*.1"
   1 [ XYZ   88  796 null      ] "page.1"
   2 [ XYZ   89  758 null      ] "appendix.A"
   2 [ XYZ   88  796 null      ] "page.2"
   2 [ XYZ   89  667 null      ] "section.A.1"
   3 [ XYZ   89  758 null      ] "appendix.B"
   3 [ XYZ   88  796 null      ] "page.3"
   4 [ XYZ   89  758 null      ] "appendix.C"
   4 [ XYZ   88  796 null      ] "page.4"