JR Pass refund in Japan

Hi everyone.

I'm heading to Tokyo next week for both work and vacation, and I just learned that I won't be able to free up the two days I had planned to use to go to Kyoto and Nara, for which I had bought a JRPass.
I know there are 2 ways to get a refund for my JRPass, one being with my travel agent (with a 28 days delay after they get back my pass, which is a bit harsh for me), and after I've exchanged my voucher with the real JRPass in Japan (and before it's been used for anything of course).

I haven't been able to find exactly how that refund in Japan works. I know I have to get to the stations who handle the JRPass, but is the refund done immediately with cash or something like that? The plan would be to use the money of the JRPass for day trips to Nikko and other things, so getting this 28 days later wouldn't be very helpful. I know they take a 10% fee for the refund, and I'm fine with that.

Anyone with experience with this? I'd appreciate this very very much!

Thanks.

I am sorry I don't have a direct answer for you BUT... I buy my JR passes through Nippon Travel Agency American in Gardena, CA. They are extremely helpful, maybe just calling and asking is the way to go? I am sure they can tell you.