Thanks, our editor helper was written back when XenForo was still 1.1.0, so it was missing some more recent editor options default values that were easy to miss.
Fixed in the next release. The helper has been slightly reworked to make sure expected editor options are still available in editor_setup, even if VaultWiki intends to disable those keys for wiki content. This should allow add-ons to modify those keys without first checking for a wiki editor context. Along those lines, $editorOptions['isWikiEditor'] has been added to make it easier for add-ons to tell.