You use shell_quote where you shouldn't. (And, arguably, you don't use it where you should.)

-e needs a path, not a piece of shell code. 

my $src_qfn = 'BulletinV3, 1 Montana 20xx-xx-xx (print).pdf_FN_TEMPLAT
+E';

if (-e $src_qfn) {
   ...
} else {
   ...
}

[download]

Or with error checking: 

my $src_qfn = 'BulletinV3, 1 Montana 20xx-xx-xx (print).pdf_FN_TEMPLAT
+E';

if ( stat( $src_qfn ) ) {
   ...
} else {
   die( "Can't stat `$src_qfn`: $!\n" ) if !$!{ ENOENT };
   ...
}

[download]

As for that message of command at the bottom, 

system( "zenity",
   "--title" => "Rename problem",
   "--width" => 400,
   "--error",
   "--text"  => "Can't rename `$src_qfn` to `$dst_qfn`: $!",
)

[download]

In reply to Re: Problems with special characters in Linux file names by ikegami
in thread Problems with special characters in Linux file names by EigenFunctions

Title:
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