If this is the only thing that needs to be done then I'd much rather have an undocumented toolkit release now than a documented one later. If it doesn't interfere with the game release of course
From what Larian has said on this topic before, the reason it's not released is because that will interfere with the game release because the editor will end up swamping QA with a wave of questions about the editor - especially if it's undocumented.
Which is why it should probably only be released with documentation
My fear is that while we may be getting an editor, Larian will forget (or have no time for?) the various other things related to it... like import plugins and export plugins, settings, guidelines and scripts for art creation etc. A guideline to import sounds/textures/models etc. Proper syntax library for the scripting system and more.
Either way, editor is coming and I have no problem if that's a week after release