"Since I have a $0 traditional IRA as of December 31st of the previous year and then do the Backdoor ROTH in January, will opening this new traditional IRA in the same calendar year in any way provoke the Pro-Rata Rule?"
Absolutely. For the backdoor process to work as desired, you must have a zero balance in traditional IRAs on December 31 of the year in which you do the Roth conversion. The pro-rata calculation treats all of your traditional IRA distributions as occurring on December 31 of the year in which they happen. Doing the rollover from the employer plan to the traditional IRA in the same year as a Roth conversion that is intended to be entirely nontaxable is a common mistake that makes the Roth conversion largely taxable and results in much of the basis in nondeductible traditional IRA contributions remaining in your traditional IRAs for application to future traditional IRA distributions until you have no money left in traditional IRAs.
Presumably the traditional IRA contribution you intend to convert to Roth is your contribution for 2024, otherwise you could just do the Roth conversion in December 2023. Keep in mind that you (or your spouse if filing jointly) must have sufficient compensation in 2024 to support the 2024 contribution. Depending on plan provisions, perhaps you could get the desired result by deferring a significant portion of your 2024 compensation to the 457(b), more than you would otherwise defer, rather than making a nondeductible traditional IRA contribution, then doing a taxable Roth conversion. The reduction in taxable income from the deferral to the 457(b) would offset the taxable income from the Roth conversion. Of course this can't be done if you are already deferring to the 457(b) the maximum permitted by the plan.
