They actually are working on it. They opened an issue with their developers about a week before you (and I) discovered the issue:
https://ttlc.intuit.com/community/retirement/discussion/multiple-ira-rmd-and-actually-distrib[produc... says, "Our programmers are currently working to improve the RMD section experience. Be sure to sign up for email updates here: Why am I getting an RMD distribution amount error?"
