@pumpkin1007
If you haven't actually filed your IL tax returns yet, wait until the 28th of Jan to try those donations again. The IL forms are not supposed to be finalized until the 27th (wait an extra day).
Filing without the Schedule G, and then amending doesn't seem workable. IF you have an IL tax "refund" without the donation, you would get the full refund long before any amended IL tax return would get processed
.....ANNNND...from what I've seen in the 2020 amended IL tax forms (2021 forms aren't viewable yet), it doesn't look to me that they allow a Schedule G addition on the amended IL tax return.
So just wait another week or two, or find a way to donate separately.