Gail S. answered 09/09/19
Experienced, Patient Adobe Photoshop CC/Lightroom Classic Tutor
Hello,
Have you tried going from the Illustrator menu to File > Open and then navigating to the file in the browser that pops up? Illustrtor should be able to open it, but you may have to convert it back to a Smart Object. I'm not sure what happens with a Vector layer saved as a PDF. But this method should work to get your file into Illustrator.
Good luck!