Please check if there any update pending for Photoshop Elements 14,
Click on help > updates
There were no updates and it still doesn't allow an import from LR 5
I have LR creative Cloud and recently downloaded adobe elements 14.
If you have Lightroom CC you also have access to the full version of Photoshop CC and Lightroom 6/CC and not buy Elements.
Can you load a Lightroom exported TIFF into Elements 14 just directly using the OPEN command in Elements?
I am not sure how to do that.
I was running into a similar problem trying to export from DxO Optics to Elements 14. I had to make sure I was exporting to the editor "Adobe Photoshop Elements Editor.app" and not the Elements cover/index app "Adobe Photoshop Elements 14.app" (the one that gives you a choice of Editor, Organizer, etc.)