Um..Quaritch is not a jellyfish, so I don't quite see your point..
It might be or not but, what I'm seeing is that Nìwotxkrr Tìyawn is trying to say that perhaps, after further sstudy we might be able to obtain immortality through a drug made from the DNA or something of the Quaritch.
Sorry if I'm yabbering on... or taking your que Nìwotxkrr.
Well that creature can regenerate itself via its DNA. We don't know if this Jellyfish actually keeps its old memories. I'm willing to bet that no. Jellyfish are extremely simple, as far as I know they don't even have a real brain. So, it's one thing being able to grow a new Quaritch based on his DNA. We know that's possible, it's called cloning. It's a completely different thing to assume his whole personality and memories were preserved.
And once again: if they could bring back Quaritch, why didn't they bring back Tom Sully?
As far as I'm concerned, Quaritch is a generic general, easily replacable by someone else from earth who's just as dedicated. He wasn't particularly knowledgeable of the Na'vi or anything else that would make him irreplacable. On the contrary: he acted rather stupid toward the end, not exactly beneficial to the RDA. Tom Sully, on the other hand, was a unique important investment, irreplacable except for his twin brother, but his memories
are irreplacable.