I would honestly leave it be. I've never lost a new nem split, and I've had them look BAD for weeks. Try feeding it a small amount of small food like mysis every 3-4 days. If it doesn't take it...just leave it be. Chances are it'll eventually take the food and that'll usually give it the energy it needs to relocate and find a happy spot.
I wouldn't dip it or remove it from the tank. You can try adjusting the flow to coax it into moving a bit...but I've had better luck just letting things play out and attempting to feed once the oral disc looks healed again.