Special:DisambiguationPageLinks displays pages that link to a disambiguation page since "They may need to link to a more appropriate page instead." But many redirects to a disambiguation page can't go anywhere better. For example, http://www.mediawiki.org/wiki/Special:DisambiguationPageLinks lists the redirect
DPL (edit) → Extension:DynamicPageList
If it indicated that the DPL page is a redirect then wikignomes wouldn't waste time trying to fix it; it's as ambiguous as the disambiguation page and thus needs to stay a redirect.
To indicate redirects, Special:DisambiguationPageLinks could use a different arrow for redirects ↳ (0x21b3) which matches the one shown on redirect pages (note RTL l10n issue). It could also/instead add the notation "(redirect page)" to them, as Special:WhatLinksHere does.