The WP DELETE FOOTER command deletes the footer element associated to the section or subsection defined by the wpSection parameter.
If no footer element exists for the section or subsection, the command does nothing.
You want to delete the footer of the left pages of a section:
C_OBJECT($section;$subsection;$header)
$section:=WP Get section(wpDoc;1)
$subsection:=WP Get subsection($section;wk left page)
WP DELETE FOOTER($subsection)