I have a chapter (??) which is intended to be printed on the inside back cover of a booklet I am producing. I want it listed in the table of contents, but with a pointer to 'insider back cover' in the ToC, not a page number. Is this possible? If so, how?
I have been trying code which looks like this:
\addtocontents{toc}{\contentsline{chapter}{\numberline{}{Mission of our organization}{inside back cover}}}
but keep getting compilation errors which read like so:
) [60] (./backmatter/01_mission.tex
! Argument of \contentsline has an extra }.
<inserted text>
\par
l.4 ...our organization}{inside back cover}}}
? q
Any guidance is appreciated. Thanks.

\setcounter{page}{inside back cover}but got this error message on compilation: ` [60] (./backmatter/01_mission.tex ! Missing number, treated as zero.
\def\thepage{}or possibly\def\thepage{Cover}anywhere on the last page.\pagestyle{empty}might help. – John Kormylo Dec 07 '21 at 15:53