Yes, I am using TurboTax Online.
I think the error is solved now.
Deleted the 1099s. Cleared cache and cookies. Re-entered the 1099s.
(The wizard for the inherited Roth IRA does not ask for the required RMD amount).
Completed the 1099 entry. (skipped review return). Viewed 1040 and there was no penalty.
Did review return, error found with RMDs - required RMD amount missing.
This time, entered the required RMD for that specific distribution only (the inherited Roth-IRA)
(Initially didn't recognize that the error checking/correction wizard was referring to only the inherited Roth IRA - both sources of distribution have same name - but clarified by looking at further details of the form which shows the distribution amount, which matched the inherited Roth IRA)
Now on view return, no penalty
Thanks again @DanaB27
p.s. good to know that it's possible to switch to Desktop from Online if need be
