According to the above list, all 3-class 777-300ER are equipped with suites. The only difference for the passenger is the ICE version. However, there is
this page on the Emirates website which shows 777-300ER configured with 12 flat beds in F and Sleeperettes in J. Out of date page?
Edit: I chatted with Emirates. The agent didn't really give a proper answer, she just repeated what it said on the website. She said I could check for each flight on the "Services by Flight" page. I asked for aircraft registration numbers for the ones without suites, but she couldn't give any. I think it's just the website that's old.