If you haven’t already done it, remove and use another port. If that won’t work, restart and try again. If that won’t work try a different USB thumb drive. You might also check for debris in the drive. They can collect dust and fail sometimes. I’ve used a paper clip to pull out pocket fuzz before.
I owned the Rokinon 14mm 2.8 for a few years. I sold it because I wasn’t using it often enough but the image quality was great. Here’s a bridal portrait I did in 2018.
Just a guess but are you trying to open the file? It may go to PS because there’s a small image file in there somewhere. If you can see the actual download, right click and select “extract all”. Then direct it to your CF drive.
I recently ordered from B&H on a Friday and received it the next day Saturday! in perfect condition. Except for them being closed so often for holidays, I love B&H. Oh and the Payboo card saved me over $100.