TextSpanner combined with Volta

[Rik Nuytten]

I am a newby with Lilypond, trying to typeset vocal music. The following snippet
did not print the string "Poco Rit." before the spanner. Secondarily, I am
wondering if the Volta spanner could be put above the TextSpanner text. I have
tried using \markup, but then the text was put too high to be presentable. I
have included the full code, inclusive \layout and \page for completeness.

Thanks

\version "2.10.33"
#(set-global-staff-size 20)     
\include "italiano.ly"
upperAllen = 
        \relative do''{
        \time 3/4
        \voiceOne
        do4 sib8 la4 sol8  
        \repeat volta 3
        {la8[( sib) la] sol[( fa)mi]
        \textSpannerUp
        \override TextSpanner #'edge-text = #(cons (markup #:italic "Poco rit" 
) "") 
        }
        \alternative {{re4 re2 sol1\rest  \bar ":|" }
                {re4 \startTextSpan \slurDown { re2  ( re4) sol4\rest sol4\rest 
        \stopTextSpan \bar ":|" }}
        }
}
firstallen = \lyricmode {
        sto -- ten zich aan ste -- nen,
        nie -- mand draagt hen.
                }
secondallen = \lyricmode {
        wordt woes -- tijn o -- a -- se waar zij ko -- men.
                }
thirdallen = \lyricmode {
        we --  ten van de stad met fun -- "da -" -- "  " -- "  "
        "men -   " -- ten.__                 }
\score{ 
        \context StaffGroup<<
                \context Staff = "upper" 
                        <<
%                       \time 3/4
                        \clef treble
                        \key re \minor
                        \context Voice = "one" \upperAllen
                        >>
                \lyricsto "one" \new Lyrics {
                                        \set stanza = "3. "
                                        \firstallen 
                                        }
                \lyricsto "one" \new Lyrics {
                                        \set stanza = "5. "
                                        \secondallen
                                        }
                \lyricsto "one" \new Lyrics {
                                        \set stanza = "7. "
                                        \thirdallen 
                                        }
                                                        >>
\layout {

                \context{\Lyrics
                minimumVerticalExtent = #'(-0.5 . 3)
                }       
                        
                \context{\StaffGroup
                \remove "Span_bar_engraver"
                }
                \context{\Staff
%               \remove "Time_signature_engraver"
                minimumVerticalExtent = #'(-3 . 3)  
                autoBeaming = ##t
                \unset melismaBusyProperties 
                } 
                
                \context{\Score
                barNumberVisibility = #all-invisible
                }  
        }
}
\paper {
        #(set-default-paper-size "a4")
%               paper-width = 210 \mm
                line-width = 170 \mm    
                left-margin = 20 \mm
%               right-margin = 30 \mm
%               #(define left-margin (* 4 cm))
        ragged-bottom=##t
        ragged-last-bottom=##f
        ragged-last = ##f
        print-page-number=##f
        indent = 0
%       pagenumber = "no"
        }