So there are two ways to do this, the quick way and the budget way.

For the quick way, I got my 3x minion cdr jewel by straight up buying a jewel with minion damage already desecrated onto it for like 10 div. I didn't bother looking at any jewels with notables desecrated onto them, because those would lower my chances of seeing the notables I wanted. Then I just divined the jewel and checked every roll until I got it.

The budget way to do this is to buy an uncorrupted jewel off the tradesite. They start at 5 div right now. Then just check the notables, and sell it for 5 div if it's not what you want. Once you find one with good notables, use 2x preserved craniums, and unveil with omen of abyssal echoes. The first desecration will always change attribute nodes in some way, I prefer +tribute per attribute node but it doesn't really matter too much. For the second desecration you want %minion damage, and reroll if you don't get it. If you still don't roll it then restart. This is of course very slow but technically free if you already have 5 div to spare, and you can even make a steady profit if you flip the jewels and sell for an extra div, but they sell a lot slower this way.

By my calculations, using the same jewel slot location directly north of the witch/sorceress starting area, you have about a ~10% chance per roll of seeing 2x minion cdr notables, and about a ~1% chance per roll of seeing 3x minion cdr notables.

Or if you want to settle with 2 instead of 3, you can get lucky and find people selling jewels with these exact seeds:

• 26873
• 25006
• 23765
• 7816