Iirc it was about 5-7% before the initial rates were tripled, so the chances of getting a recipe should be 15-20% right now.
The 50 fragments requirement was lowered with the episode 11 patch.
First Refuge now drops fragments, too, and requires 10 per item (this cube drops crafted equipment now if I read that correctly, no longer recipes).
Asio and Wastrel raid require 20 fragments.
Ignas Raid was lowered to 40 fragments (not quite good but still better than nothing I guess).
It’s not as bad anymore, but still tedious.
Let’s see what will happen to other cubes in the future…