I would point to the particles possibly being a cure for things like Irumodic Syndrome (humans)
Which is the result of a genetic defect, I fail to see how reversing age and regenerating optic nerves means the particles can flat out rewrite DNA.
No to mention that the federation would consider that illegal, what with the whole ban on genetic engineering.
and Bendii Syndrome (Vulcans)
assuming that this isn't also the result of a genetic defect. We don't really know what causes Bendii Syndrome, so its a bit presumptuous to claim what might be able to cure it.
This is why I believe that after a very brief "review" by the Federation Council , their original orders to collect the particles would be implemented. If not (and contingent on the matter becoming public) the Council representatives would likely be recalled and replaced by their respective home worlds and the new Council would have the particles collected.In the real world, if a corporation or group of people were sitting on the cure for cancer and refusing to make it available, people would be foaming at the mouth and screaming for government intervention and rightly so.
And yet there is no evidence in any Star Trek production that the particles are being used by the federation, no looks any younger and people still die from stuff they're allegedly supposed to prevent death from.
Most importantly Picard and his crew haven't been court martialed and are still on the Enterprise except Worf who got an ambassadorial job to a major federation ally, in fact later Riker was getting his own command.
The other reason I doubt it is that the guys writing it who made Dougherty and the Son'a the bad guys WERE STILL RUNNING THE FRANCHISE.
So they are going to go back on what they wrote why exactly?
Because given past history fans complaining on the internet doesn't do crap.