While the Elders would be immune to the OE disintigration as they are essential to the universe, these elders in particular are chumps and would lose.
Gardner can control plants - big whoop. Darkseid would OE or rip through anything thrown his way.
Collector has lots of gadgets, nothing that's going to put Darkseid down for the count though.
Obliterator has some nice weapons, once weapons are gone he has jack. Just like Silver Surfer, Darkseid could destroy the weapon pack and then Obliterator will be useless.
Possessor is decently strong but isn't on Darkseid's level. He loses.