nhfox,
Yes, do enter the entries on your 1099-DIV into the TurboTax "Dividends on 1099-DIV" dialogue. 1099-B forms are for actual sales you made of equities such as stocks and bonds or mutual fund shares.
I have a similar problem - a broker 1099-DIV that reports Capital Gains from a mutual fund but no 1099-B data providing any specific trade information. TurboTax Business is insisting on 1099-B brokerage transaction information.
When you enter into the capital gains section in TurboTax Business, you will initially be asked to enter individual investment sales information. However, if you leave that entry blank and continue on in that section, you will see an opportunity to enter capital gain distributions on the screen that says Capital Gain Distributions:
That is where you should enter the capital gains reported on your Form 1099-DIV.