CG have been asked to provide this information before, but they never have and probably never will. Though, if I could offer one ray of hope, they never used to tell us the odds on character shard drops paid for with crystals / real money either but now they do (though I suspect they were legally required to provide this).
As for the drop rates, the community has figured them out by observation. Shards have a 1/3 probability to drop. We don’t need CG to confirm this because all the data points to this, and anyone who tracks drops over a period of time will see the same. Gear depends on the colour, as does signal data. Omicrons are much much lower than pretty much anything else.
Even when something less common happens, like a Galactic Chase for a new ship, the community have worked out the drop rate within a few hours of the event going live. I remember one particularly unhappy evening on the forums when a Galactic Chase on ship energy had a 2% per energy spend drop rate when the previous Chase on cantina energy had a 4% drop rate.
Cristoph’s data is very interesting (I think I may have contributed to it when I tracked thousands of results of mod farming) and I think you’ll get the information you want from a source like that long before CG ever say anything on the matter.