How to get dot to move with note

[Nick Payne]

Lilypond 2.13.3 on windows. I've come across a problem in a piece I'm
setting and can reproduce it in the following example. When I shift the
dotted half note in the bass voice to avoid a note collision, the dot
doesn't shift with the note. How do I move the dot. I tried doing the same
override for DotColumn as for NoteColumn but it had no visible effect.

\version "2.13.3"
\relative c' {
\time 3/4
<<
{
e'2.
}
\\
{
c8[ <g e> <g c><g e> <g c> <g e>]
}
\\
{
\once \override NoteColumn #'force-hshift = #-1.3
c,2.
}
>>
}

Nick