So it was not a recharacterization as originally stated and was instead just a taxable rollover from the traditional account in the Keogh plan to the Roth IRA.
Near the end of January you'll receive reporting the distribution from the Keogh plan a Form 1099-R that you must enter into TurboTax. If the Form 1099-R has code G in box 7, indicate that you did not roll the money over to a Roth 401(k) but that you did roll the money over to a Roth IRA. If the Form 1099-R instead has code 1 or 7, indicate in the follow-up that the money was from a qualified plan, that you moved the money to another retirement account and indicate the amount that you converted to a Roth IRA. In either case TurboTax will include the taxable amount on Form 1040 line 4d.
The Form 5498 showing this as a rollover contribution simply acknowledges that you completed the rollover from the Keogh plan to the Roth IRA. The Form 5498 itself is entered nowhere in TurboTax.
