As requested on https://imcdb.opencommunity.be/forum_topic-9675-85695-AKAs_in_our_main_site.html#p85695 now the non-admin contributors can add/edit aka titles on movie pages, but only when there are no validated vehicles on them.
So they can do it before adding vehicles, or after adding vehicles before an admin validates them.
When the admin validates the vehicles he can check if there is nothing weird in the aka titles