That does explain it. You didn't previously mention that you had split the rollover between two destinations, so I had assumed that you did not since just rolling over the $6.37 to the Roth IRA (along with the other $90.88 of pre-tax funds that you rolled over to the Roth IRA) would have been far simpler without any significant tax consequence.
To accommodated TurboTax's limitations on dealing with a code-G From 1099-R that reports rollovers to the two different types of IRAs, you must split the Form 1099-R into two for entry into TurboTax. The one for the rollover to the Roth IRA will have $8,316.77 in box 1, $90.88 in box 2a and $8,225.89 in box 5. The one for the rollover to the traditional IRA will have $6.37 in box 1, $0 in box 2a and a blank box 5.
