Forms 1099-R reporting distributions from IRAs are reflected on lines 4a/4b. All other Forms 1099-R are required to be reflected on lines 5a/5b. Your 401(k) and 403(b) are not IRAs. The Forms 1099-R with code G in box 7 are from the 401(k) and 403(b), not from an IRA. Your description of where the amounts are appearing seems to indicate that TurboTax is behaving properly.
