RhythmicStaff vs. repeat bar-aligned markup

[Richard Opheim]

This one's beyond me. I want to insert some markup that aligns with the repeat bar instead of a musical note. It so happens that there's a RhythmicStaff above the main staff and over the measure where the repeat bar is, so my repeat bar-aligning markup text ("Repite ad lib.") now appears above the RhythmicStaff, instead of above the main staff with the other markup ("Guía"), as it would if there were no RhythmicStaff.

Here's some code that will reproduce my problem:

<<\new Staff = "main"
\with {\override VerticalAxisGroup #'minimum-Y-extent = #'(-2.5 . 2.5)}
\relative a { \clef "treble" \key c \major \time 6/8
%{measure 1 %} <<{\repeat volta 2 {a4 ^\markup {\bold {Guía}}c8 ~ c8 a8 [ a8 ]
%{measure 2 %}  g8 a4 a4.}}
\new RhythmicStaff \with {alignAboveContext = #"main" fontSize = #-3 }
{b4 b8 r8 b8 b8 r8 b4 b4 b8}>>
\once \override Score.RehearsalMark #'break-align-symbols = #'(repeat bar)
\once \override Score.RehearsalMark #'self-alignment-X = #RIGHT
\mark\markup{\normalsize Repite \normalsize\italic{ad lib.}}
%{measure 3 %} e1^\markup {\bold {Guía}}}>>

Can I get the "repite ad lib." to align horizontally with the "Guía"?

TIA

Richard Opheim