should no be a problem the track should show up just fine, but waveform will not show up right away as the player will need to analyze the song after that it should work just as if it already was exported by record box
But don’t put it in the “Content” folder created by RekordBox on the stick.
Put it appart.
If you put it in content folder, you won’t find the track, because the CDJ is not looking for files but for a kind of list of exported tracks i presume. And because you didn’t export it via RekordBox, it won’t be on the list and you won’t find it.
And when you put the track on the stick (not on the “Content” folder created by RekordBox, i repeat) you should see an option named “folder” when you browse on the CDJ. It’s in it. (at least that’s how it works on my CDJs)