Sorry, I was not paying attention to what you were really trying to do ...

In that file, you only need to change the 1 line:
Code:
 if (SHOW_BANNERS_GROUP_SET4 != '' && $banner = zen_banner_exists('dynamic', SHOW_BANNERS_GROUP_SET4)) {
to read:
Code:
 if ($this_is_home_page && SHOW_BANNERS_GROUP_SET4 != '' && $banner = zen_banner_exists('dynamic', SHOW_BANNERS_GROUP_SET4)) {
adding what is in red will only let the code run if on the Home page ...