Okay, just so you all need reminding -- Spoilers!!!---
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Now that that is cleared up, I have the Mace of Disruption +1 and illithium ore (from jerlia, unpure) and I went to cromwell because I heard he uses those to make Mace of Disruption +2, but he didn't mention it. Is there something else I am missing or does he not do that? Or what do I need to do in order to get the upgrade?

if cromwell can upgrade it he should tell you what he needs. it might be tob upgradable

its not a ToB upgrade, but ive never made the mace, so i can't help you.

You need the pure stuff. To get it you have to do the side quest where you go to see Jerlia's illithium connection.

Blast then! I already gave sir Sarles the pure stuff. Is there any way to remedy this?

Legitimately? Reload and...
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Spoilers
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... give Sarles the impure stuff. See him flip off and take off, go to the Temple and collect your reward( do not worry, it will make sense), then visit Cromwell to make your spanking new Mace of Disruption +2.

Hmmn... is there any un-legitamate way, such as a creation code for the pure illithium?

CLUAConsole:CreateItem("MISC5K")

You could always kill Sir Sarles...

I am not sure whether killing jester Sarles will help. I tried to pickpocket him after pretending to give him the pure ore once. No success. The ore isn't in his inventory after giving it to him. Therefore, killing should not work, too.
One final note. You must not bring the pure ore to the jester when you plan to keep it. If you have both the alloy and the pure ore in your inventory at the jester, the jester will ignore the alloy and take the pure ore. Therefore:
a} Gain the pure ore.
b) Store the pure ore at a safe place.
c) Catch the alloy and go to Sarles.