Hi @scottthesecond, welcome to the community 
I am so sorry to hear you’re having trouble here. From giving this a quick go on my end I could confirm the problem and shall add it to our internal bug tracker.
It failed for me until a few minutes ago and just when I was talking to @Nivb_6 about the error it started to work again for me. So I wonder if this might indeed have been a temporary problem on Xero’s end. Would you be able to re-test this on your end (and double-check you’re using a valid Organization ID)?