why not? they can always click the link on the quote to find the real quoted post.
how if the Quoted post is not found ?(deleted)
then that's the poster of the quoted post and mods' business. afaik deleted posts go to the trashcan and mods can view them.
IIRC when I asked hilarious about a deleted bump , he said only admins can access it , so wouldn't be sure on that statement.